Things l love: Very easy to set up and gives great feedback. Support was very helpful in answering several questions regarding certain measurements and their meaning. Things that could be better. Different strap options. Although the silicone rubber in nice would prefer to have a fabric option as well. Also, having only one strap size is a problem. I almost had to send back because I have large wrists and it barely fit. Additionally, battery life of 1 day is really a drag, but with the O2 sensor and all of the other readings it's taking it probably drains the battery a great deal. Also, autodetecting exercise and sleep would be nice too. It would have been nice to know that sleep tracking was an extra charge when I purchase the strap.