Well, since I've relied on the reviews of others at Amazon, I suppose it's appropriate that I take the time to share my experience with the rest of you.

I have for decades had a devil of a time with both regular insomnia and with periods in which I didn't sleep at all for days. So the notion of a little star-trek like device to sample my brain waves and allow me the feedback to possibly sleep better seemed like a neat deal.

And indeed, it was Amazon's "deal of the day" marked down to $199 on the bleary morning I ordered it last month, after several successive nights of less than 2 hours' sleep. Their featuring of the item seemed like kismet, and $200 for the possibility of improving my sleep seemed like a pittance.

I've now used it for several weeks, and will be returning it. I'll try to list the pro's and cons here:

Pro's: It's not uncomfortable to wear. I consider it brilliantly designed, the interface intuitive, the memory card easy to remove and replace even without looking at the slot, the way the recharging cradle seems to have a magnetic lock which enables quick and accurate replacement. The support staff are courteous and prompt in answering questions. The web interface is a nice bonus and graphic display, although I'd have preferred a simple home program. But they do let you download the info after you've uploaded it, where a subset of it could be put into an excel spreadsheet if anyone wanted to.

Cons: It doesn't work and is bloody useless.

I suppose your mileage may vary, and perhaps I have an unusual brain, although past MRI studies haven't shown any mutant extra lobes or anything, which was vaguely disappointing though expected.

But the device just seems to make stuff up. It gives the impression of a Chinese knock-off of a working device, like those MP4 ipods you can get on ebay which work for a day and will only store three songs before the actual ram is full.

Specifically, IF I am asleep, it will dutifully create a graph showing periods of REM, deep sleep, light sleep, etc. And I could look at that and go "wow, look at this great telemetry". Except that it does exactly the same thing while I'm awake. Indeed, even when I put it on with my eyes open, it immediately reports I'm in REM sleep. Last night due to an injury, I lay there wide awake for nearly two hours. Annoyingly, I was able to pick up the recording device and see, in real time, that I was in REM sleep, or in light sleep, and hadn't woken up at all. I could actually stare at it as it logged my sleep status every 5 minutes, and see it tell me I was asleep. Bottom line, it considers me to have been solidly asleep for over 7 hours last night, when I was only unconscious for three.

Nor was this the first time this was apparent. The first couple nights I couldn't help noticing that it STARTED me in REM sleep as soon as I put it on. As long as I wasn't talking out loud, it didn't consider me awake. Contacting the polite and upbeat Zeo support staff via email, I noted this, and was advised that it was not good sleep hygeine to stay awake and think about things. Wow, why didn't I think of that? No, I explained, I agree that insomnia is antithetical to sleep rather by definition, the point is that your invention doesn't work. They assured me that they would contact their tech person and get back to me.

Within a day I got back their tech advice: the Zeo was designed to work on normal healthy brains. If it didn't work on me, the implication went, then my brain wasn't normal or healthy enough to meet the standards of its product. So it wasn't their PRODUCT that didn't work, it was my brain.

What provided a colorful backdrop for this was that although I'm a 59-year-old insomniac, the machine was giving me the "Z score" of a 20-year-old olympic athlete. A night lying there getting terrible sleep and being awake nearly constantly would show zero wakings - not even being awake when I put the thing on - And so would say that I got 8 hours sleep including 4 hours of REM, and give me a sleep score of over 90, not only counting me as being asleep the whole time, but giving me bonus points for all that REM sleep.

I know, too, that it will say I'm in "light" sleep while I'm conscious, because last night, having nothing better to do, I held it and stared at it, daring it to continue to tell me I was in light sleep. But after five minutes of staring, it did. The ONLY incorrect thing it has NOT done is report that I'm in deep sleep while I'm awake.

"Many times we don't remember sleeping when we really do", notes the Zeo techs. OK, true enough, but again, your product doesn't work. It considers me in REM sleep or light sleep from the moment I put it on. I suppose I could consider the philosophical proposition that I have never yet in my lifetime been actually awake, which might explain a lot; but I'm not sure why I'd dream about buying a product off Amazon that doesn't work.

Frankly, since the thing is wildly inaccurate while I'm demonstrably awake, I'm less inclined to trust what it says I'm doing when I'm actually asleep. Ironically, I get worse ZQ scores when I sleep better, because I'm actually sleeping and don't lie there in the dark trying to sleep for 9 hours. I've taken to giving the ZEO display a display of my own upthrust middle finger each morning as it gives me a 95 for a terrible night of sleep and only a 64 for the best night I've had this month.

So to sum up: it is apparently useless for people with brains like mine. Inasmuch as there is nothing else notable about my brain, it may be useless for a lot of people. In other words, how do you know it isn't just making stuff up? The novelty of seeing a graph of your sleep stages is cool, but there is no way to tell whether it corresponds to objective reality. Ultimately it may be a good placebo for those who have more faith in machines than in their own fallible protoplasm, but again, and to me quite salient: it doesn't work.

I will note here that if the good folks at Zeo wish to tweak the product so it DOES work, I'd happily buy one even at the normal price. I hereby offer to be a test subject for them if they build a "mark II" version that will actually do what the current one purports to do.

So my next adventure will be sending it back, and I'll report back if that becomes any sort of adventure. Of possible concern is the fine print: they offer a 30-day money-back trial, BUT the machine must be returned in "salable" condition the same way you received it. Say what? You can't even unpack the thing without tearing open several plastic bags, and you can't plug it in without unwrapping the cord, etc. I guarantee that although I will return it in its pristine unworking condition as good as it ever was, that they'll have a hard time reselling it without repackaging.

Also, I note that unlike my other Amazon purchases, I can't just go to my account and do a return, I have to go through the company itself.

So to sum up, I think two stars is a pretty charitable score for a product that doesn't work. It's a masterpiece except for that little fact.

UPDATE 3/5/10: I asked for an RMA and they sent me one, but noted that I had to cover the return postage. So I decided to invoke Amazon's A-to-Z return policy and submitted a claim to make sure I got the full refund. Very quickly thereafter I got a nice note from Zeo saying they'd send me a prepaid UPS label to return it - which they quickly did - and assuring me that they would give the full refund. So I thank them, and I also thank Amazon for their policy - it never hurts to buy through Amazon when you have a choice.

Overall, I am satisified enough with my Zeo to keep it past the 30 day return period. However, if there was an alternative to the Zeo I would return this and try the other product.

I too have sleep Apnea, and actually stopped using my CPAP machine for a year after I first got it. My feeling was that the machine was waking me up more than Apnea was due to it shutting off and mask leaks. A second sleep study revealed an outright dangerous situation, and they had to stop the test after an hour and put me onto a CPAP machine. I still have a choice of masks, so I wanted to see if a different style mask would still cause the problem. The Zeo pretty much has ruled out the CPAP as being a problem, I think. More below.

I also have been trying to stop taking an anti-anxiety medication. The last time that I tried I developed Syncope, a condition where you randomly pass out and fall down. It's unclear whether the cause was the medicine, the Apnea, a combination of the two, or something else, but the doctors blamed it on the apnea. The Zeo, however, has shown me that although I fall asleep faster with the med, I don't go into REM or deep sleep hardly at all. It also showed that as I tapered down the med, it took me longer and longer to fall asleep, 1 then 2 then 4 hours, but it was a 'good' sleep. I could determine after a week or so that my sleep patterns went back to 'normal'. The first time I tried to stop I started nodding off uncontrollably at my desk, and at least then I knew enough about what was happening at night to cause it.

I couldn't have tracked and found out these things without the Zeo, and if it weren't for some other issues I would recommend it without hesitation.

There are some accuracy issues. I know that I have been regularly waking up and the Zeo does not record it. This is really important to me to monitor the above conditions, and in trying to isolate myself with a sound machine or 'sleep music' cd's and seeing if something else is waking me up. For instance, I have a feeling that when I turn on my side the CPAP mask is hitting the pillow and nudging away from my face, waking me up, but I can't tell for sure.

What really bothers me more than anything is the fact that you can not get an accurate representation of your sleep without uploading your sleep data to Zeo. There is no software to run on your PC to see your sleep info, all of the displays run in your web browser from the Zeo website, and all data is kept there as well. If something happens to Zeo, you are left with nothing but a really expensive alarm clock. The display on the unit does not show the time to fall asleep nor accurately portray deep sleep, and cannot be saved or printed.

Some people have posted their concerns about privacy of information as well. I personally don't have a problem with it, but Zeo sells or will sell or is trying to sell or is thinking about selling (they're not sure) to third parties. One person pointed out that his sleep data could be subpoenaed in the event of a traffic accident or something, and they could say you were not getting enough sleep and caused the accident. They added an 'opt out' option to their web page, it's not very prominent but it's there. The individual stated that he would just use an alias when setting up the web account, probably a good idea. Privacy issues aside, your sleep data is encrypted and you can not read it off of the SD card. You can, however, upload your data to the web site and download a .csv file back so you can import it into a spreadsheet. It does not, however, resemble anything other than a string of numbers, you could not read it or graph it. None of these issues are readily available for reading on their web site, you need to dig around a bit and find a blog that is addressing them.

Which leads me to my last little gripe. When I posted in their blog that it was a problem not being able to see the data locally, and I could not use the device if they went out of business, their response was that they were on the 'Today' show. Ok, but when I opened up the Zeo box and checked the contents, I was short a sensor pad. When I emailed them about it I was told that they stopped including it to save money since they lowered the price. Doesn't sound like a financially strong company to me if they have to exclude a little cheap pad.

So, if it wasn't so useful, even with the problems mentioned, I would return it. If I had known about the data being on the website only I would have never bought it. But, there really is no alternative that I know of (especially on the 'Today' show).

I have trouble sleeping and thought I would try the Zeo. The MyZeoe website comforted me with language of "30-day risk free trial". I purchased the unit and began using it.

However, after using it for two weeks I realize there is a limitation in the device. Basically, it sometimes takes me a long time to get to sleep at night. The Zeo, however, tends to think there is no way it could take a person 3-hours to go to sleep and truncates my time to sleep to 12 minutes.

No big deal, the Zeo is not for me. I started the return process and this is part of the exact email I received back from Zeo:

"Returned merchandise must include all original accessories, literature, documentation and packaging in the same saleable condition in which you received them. Refunds for returns will only cover the purchase price and any sales taxes charged. Refunds will be processed within 30 days of receipt of your returned product, in the same form of payment as your original purchase. Refunds will not be made for any shipping and handling charges.

Damaged merchandise, cosmetically or otherwise, may be subject to a restocking fee equal to 30% of the price paid (not including taxes). You are responsible for and must prepay all return shipping charges and shall assume all risk of all loss or damage to the product while in transit to Zeo."

Feels much different than a "30-day no risk trial" that they spoke about on their site. Thought I would warn folks about this...

That being said, I like the concept of the product and wished it had worked for me.