This review will hit upon several issues, especially as they relate to other reviews here: size, heat and speed, efficiency, and satisfaction.
Some of the reviews on this page made me nervous about both the Citiz and the Pixie. I have been using and loving my Nespresso Esenza for 3.5 years, and it has never had a problem--it doesn't leak, it makes perfectly hot espressos, the crema on the espresso is excellent, it has a nice, simple design, and its footprint is perfect for my apartment countertop. A flawless machine in every way. Some of the reviews here for the Pixie and the Citiz worried me that Nespresso had dropped the ball and let their quality slip. This is not at all the case.
My Pixie is a wonderful addition to my small, private office. The water-cooler station in my faculty lounge has a Keurig, and I hate it. The Keurig functions just fine, but the taste (no matter what "k-cup") is horrible, and I really prefer espresso anyway. I was going back and forth between the Pixie and the Citiz, but went with the Pixie for two main reasons: the size, first off; secondly, I visited a Nespresso boutique and they explained to me that the Pixie is the hottest and fastest, as well as the most energy effcient of their machines.
As to the size, it's perfect for sitting on my desk (and L-shape desk). I have plenty of room for the machine, some espresso cups, and all my other stuff, and plenty of workspace left over. The other thing I liked about the size, in contrast to some of the other reviews here, was that I liked the smaller water tank. Since I'm the only one drinking from this machine, I prefer to change the water more frequently because it keeps it fresher. Besides, the 24oz. tank makes at least 12 espressos, so I'm changing the water once a week, maybe twice. This isn't a realistic problem or inconvenience. It takes me longer to pee. If you're putting this in a kitchen where several people will be making drinks, this might be an issue, but it's important to keep in mind how much your use will tax the 24 oz. reservoir. And anyway, it takes only a minute or two to refill the water tank, especially on the Pixie, which is so fast!
In terms of the speed and heat, it is really fast, warming up from being powered off to ready for espresso in about 20 seconds. My Esenza can take a full 1-2 minutes, depending on how long it has been cooling. As far as heat of the coffee is concerned, the reviews about how it doesn't make a hot drink are nuts. The espresso that comes out of this machine is much too hot to drink right away--it's steaming hot. I've made the mistake of taking a sip too fast and it burned my mouth. I can't imagine many people needing to take a shot of piping hot espresso. You should be sipping it and savoring the flavor. If it's too hot, you won't be able to enjoy it. In fact, one of my few complaints with the Pixie might be that it's too hot: the crema on its espressos is not as good as with the Esenza, and I wonder whether that's due to the heat. If it's not due to the heat, it might be to do with the speed. This machine quick, making an espresso in about 10 sec. (starting with my pushing the button to a full cup).
Efficiency: one of the things I liked about the machine was the auto-off function. It automatically shuts itself off after 9 minutes of non-use (again, it only takes about 20 second to heat back up and get ready for your next espresso). I thought this would be perfect for my office, and I like that it's looking to save some power. The more cynical reviewers here would probably say that it doesn't matter that it powers off because the Nespresso system is so wasteful anyway--this is true...if you're lazy. The Pixie's body itself is made of recycled capsules. The capsules are perfectly recyclable. All you have to do is scrape the grounds out of them. Is this a pain in the neck? I little, but I used to just save them up, do about 30 at a time, and it would take me 10 minutes; I use a butter knife. I probably spend as much time in aggregate rinsing all my plastic and glass bottles and jars before they go in the recycling bin. Here's the best part: if you live near a Nespresso boutique, a Sur La Table, or a Williams Sonoma (perhaps other retailers, too), they have recyling stations for the used capsules. You don't need to clean out the grounds; you just take in your spent capsules and they ship them to Nespresso for extraction and recycling. This is a perfectly green enterprise, and certainly more eco-friendly than all the Starbucks cups we all just throw away.
This is my second Nespresso product and I am a most satisfied customer. Everytime I have dealt with Nespresso customer service, either to order capsules (though I mostly do this online or at Bloomingdales, where I have a boutique), or to ask a question, they are friendly, professional, patient, and knowledgable. My original Esenza machine came with the milk frother accessory. After about a year of use, the milk frother (which is a separte unit from the Nespresso machine) stopped working. I called just to order another because I had around that time received an email about how it was time for me to descale my machine, and they had some special going that if I ordered any capsules, they would include the descaling solution for free. So, I called, and ordered some capsule and the descaling solution, then said I also needed to order a new frother. She asked me to hold, came back a couple minutes later and explained that the frother was still under warranty. She overnighted a new (not refurbished--brand new, newst model) frother and included my capsules and solution in the same shipment. For free. All I paid for were the capsules. New frother, descaling solution, overnight shipping...FREE. That is serious customer service, folks. The people in the boutique a very nice and informed, too. What I also like is that Nespresso tracks your capsule ordering, so they know about when it's time to descale. I don't even think about it--they send me an email, I know it's time based on how many capsules I've gone through. Ordering is extremely easy online, and two day shipping is their standard method, so if you're just a little thoughtful, you'll never be without. As for the proprietary capsule, who cares? It's 50 cents per espresso (only 65 cents for their limited edition). Cheaper than any coffee shop, and it's an espresso far superior to, say, Starbucks, Coffee Bean, or Caribou. Unless you demand artisinal espresso everytime, I can't imagine this not being sufficient, even for true espresso lovers.
My satisfaction with the Pixie (and the Esenza and Nespresso generally) are through the roof. The only reason I'm not giving this machine 5 stars is because I think the Esenza might make a better espresso (the crema specifically) and Amazon won't let me give it 4.5 stars. Interestingly, the Esenza has a much lower price-point, but it's slower, not as hot, and not so eco-friendly. The Esenza's design is also not as slick. I love the way my Pixie looks. I get compliments and intrigued oos and ahs from colleagues and students all the time. Too bad for them I won't share. I'm adding a photo of the Pixie in use. It's the one with the pretty blue cup.