I’d echo pretty much everything Pinkster said. Mine’s been excellent so far (3 months). I wear mine pretty much all the time and use the GPS for running and cycling. I’ve even used it in the gym for the treadmill and weights, which actually works OK. It’s doesn’t recognise all of the weight exercises but you can manually input those it misses.
For the money, I don’t think there is better out there. If you spend a fair chunk more you can get the Samsung S3 Frontier, which is “smarter”, but I didn’t see the point and I’m happy with the choice I made.
I get almost a week out the battery if I don’t use the GPS, but it’s rare that I go through weeks without using it. The GPS does cane the battery life, but it’ll easily do a 4 hour ride and still last a couple of days.