I'm fairly disappointed. When it works, the data is really interesting. I'm on my second unit, and they've both been really really flaky, mostly battery issues as far as I can tell. Annoying to use (constantly have to find a little tiny switch and turn it of and back on again).

I guess for a $49 sleep monitor what do I expect? My sense, having had a taste for what it could do, is that I'd rather pay a bit more if it meant more reliability. It's frustrating when your data collection is thrown off by a lost night, or when the alarm doesn't go off at the right time because it lost its connection.