I've had the 2.2l for almost a year. It's been problem-free. Again, I use nothing but distilled water (gallon jugs are a buck apiece at the grocery) so I don't have to clean it. The instructions talk about how to do descaling if you use tap water, and it sounds like a real nuissance.
I like how quickly the 2.2l can raise to different temperatures. The 4l is much slower, taking 4-5 minutes to take water up to boiling from standing by at 175 degrees.
Both sizes give off a little heat, and the outside stays warm but not hot. I didn't see any real jump in electricity usage with the home one, so I'm assuming the insulation is good.
I'm not sure what to add, other than the fact that both my pots are silent, don't leak, and basically do exactly what you'd expect them to.