Update 2/15/16
This will likely be my last update. After initial success with voice commands, Alexa has seemingly gotten worse, not better at working with the harmony. Alexa will report back 50% of the time that the harmony is not responding. After many reboots and harmony skill re-ininstalls, I'm sad to say that no improvement has been made over the last 1-2 months. With that being said, commands run through the 3rd party service, IFTTT, have run flawlessly. If you are buying this product strictly for voice integration, you may want to wait until all of the bugs are sorted out. I'm sad to say I'll be taking away a star. For such hype and initial promise, it's disappointing to see that the product still has many shortfalls.

*Update 01/12/16*
Additional Amazon Alexa support is here! You are finally able to control volume/channel using just your voice if you own an amazon Alexa product (echo, echo dot, etc.). And while not as intuitive as controlling the volume on the echo itself, you can use the following voice commands to control your TV, sound system, etc.
-"Alexa, ask Harmony to turn up the volume"
-"Alexa, ask harmony to mute the volume"
-"Alexa, ask harmony to turn on the ___channel" (using channel favorites)

This is just a short list of the commands added, but functionality is improving almost every month. Aside from the voice updates, stability and reliability is drastically better through the native Alexa skill, so take older reviews complaining that voice commands don't work very well with a grain of salt. To enable these new commands, you have to download ANOTHER Alexa skill called "Harmony" in addition to the previous one called "Harmony—Optimized for Smart Home." If you have any further questions about the hub, leave a comment on this review, and I'll try to answer it as fast as I can.

***The Review***
I decided to brave the "horrific set-up" reviews and buy this in hopes of ditching my numerous remotes once and for all. The verdict? So close! While I initially planned on only buying the hub without the remote for use with my Amazon Echo, the lack of native support for the Echo and being forced to go through IFTTT recipes makes this task extremely unreliable. Overall, I was pretty surprised with how easy the setup process was and would recommend for anyone with a relatively simple setup that's looking to clean things up. *One thing to note, this product is definitely for someone who has some previous knowledge or experience with setting up electronics. For everything to work properly, you'll have to perfect the setup sequence and potentially add some action delays. But have no fear, I have a step-by-step guide for how to do just that below.

Here's the breakdown:

THE SETUP: (Samsung TV, Vizio Soundbar, Xbox)
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•BEFORE you buy this product, go on the harmony website and check to see if your devices are compatible. This is the #1 cause of half of the frustration seen in the comments. If your devices are supported, the setup process should be fairly simple.
•I used the mobile app to complete the setup because I did not get the accompanying remote. Simply search the model number (often found on the back or bottom of your device) and that's it...No tapping the channel up and down buttons repeatedly for what seems like hours till your device turns off. Just find and press enter.
•Last thing to note, and maybe MOST importantly is the use of delays to make sure everything works fluidly and correctly. If you have a device that takes a while to boot up (Like my Vizio soundbar), if you do not add a delay, when the device turns on, the Harmony will have already issued the command to switch to the correct input before your device was fully functional..thus, you'll get angry because now you need to go find the remote to turn on the thing you bought the harmony to replace. No one's happy.

Here's how to add a delay to one of your devices through the mobile app:
1. After you've gone through the Harmony setup and created an activity (ex. Watch TV), select the activity you wish to add a delay to.
2. Select "Edit Start Sequence" and scroll to the bottom and select "Edit Entertainment Devices".
3. Scroll to the bottom again and select "add delay".
4. Choose the amount of time you want an action delayed (in my case I want my Vizio soundbar to wait 3 seconds after powering on before trying to change inputs).
5. Order the delay to the right position in the sequence using the drag and drop tabs on the left of the screen... and you're done!

The Harmony Itself:
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•First thing to note is its size. It's about the size of a drink coaster, which was much smaller than what I was expecting.
•The device is made out of plastic but feels reasonably substantial and well made.
•Because of its small profile, you could easily leave the hub out on your entertainment center or what have you without much notice.

The Gripes:
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•OKAY, yes... the setup could more intuitive, and the use of delays and re-ordering your activity sequences shouldn't be buried in endless mobile app menus. But if you take the 30 min to set everything up right, you shouldn't have many issues in the future
•I bought this to use with the Amazon Echo, but I would say the IFTTT recipes needed to make this work only work 50% of the time. They have apparently begun beta testing native support with the echo, so hopefully this problem will be resolved in the coming months, but as of right now...not worth it.
•My last gripe is that it takes a while for the harmony app to connect to the hub. So for people without the remote, you could honestly manually turn everything on in the time it takes to open the mobile app, connect, and choose the activity you want to perform. Hints: WE NEED NATIVE ECHO SUPPORT (If anyone at Logitech is reading this)

Overall, the hub shows immense promise, and with the remote, could make this a well-worth product. HOWEVER, If you are like me and planned to use this with the Amazon Echo, I would wait till native support arrives. In the meantime, look at the Samsung Smart Things workaround for more reliable performance than IFTTT recipes.

I think the setup must have changed significantly in the past year or so. I was able to get all 5 of my devices entered through my phone and working in less than 15 minutes, which included me having to redo my Wii U because I left the Wii on during that process and the hub paired the Wii twice instead of getting the Wii U. I didn't need to learn any buttons, all the buttons on the physical remotes were available automatically. I could also turn the system off from anywhere in the house, which isn't at all necessary, but pretty cool.

9 month update...
When the hub actually does what it's supposed to it's really nice. However, very frequently I have to close and restart the app to get the TV to respond. I'm not sure what the issue is since I can see the hub lights registering my commands, but nothing happens until I close and restart the app. It's not the phone either I see this behavior on all 3 phones. It's also not the TV since it happens across all devices as well. So this leaves me wanting desperately to change the volume because it's really loud (since Netflix can't regulate show volumes for us) and I have to run to the TV because the hub isn't sending the commands a couple times a day, which is the entire point of having a remote. And in my opinion, a "remote" that works 90% of the time (especially for this much money) is a terrible remote.

Also, I synced a Wii and WiiU to it as well. It's nice that you can do this, but it's completely useless because the phone becomes controller 1 but can't actually control the the system. I tried to resolve this with customer service, but nothing worked. According to them, if you hit "Disconnect" it will remove the phone as a controller, but it does not. This means you have to re-order the controllers on the Wii. So I've removed turning in the systems in the action since it takes longer to re-order controllers than to turn it on with the controller.

There is potential here, but a lot is missing in this application. The game system thing is annoying but livable. Not working 10% of the time is unacceptably high for me.

I have a fairly new 60" Sharp TV. Although it recognized my other components, Yamaha A/V, Xfinity cable box and Amazon Fire TV, for some unknown reason this device refused to recognize or operate the TV in any fashion. Very disappointed as I had high expectations

When I first set this controller up with the Harmony Smart Control, I loved it but if anyone in the family would power one of the controlled devices by another method it would require an unreasonable effort to get them back into coordination. It appears to work using a series of macros rather than a feedback system. So, it is not really a smart control, bummer. I filly gave up and disconnected the system and it will likely end up in the trash.

Using this device with Alexa to control TV's - History - You go to light switch hit it and 10 out of 10 times the light comes on. You tell Alexa to turn on the light 9 out of 10 times it works. You tell Alexa to turn on the TV 9 out of 10 times the TV does nothing. countless hours troubleshooting no change. AVOID AT ALL COST. Also both Amazon and Harmony refused to refund due to 3 days past refund period.

Something that should make life simpler was way too complicated to program. It did not sync up well with my tv or soundbar, and was not compatible with most smart plugs or smart bulbs.