I've had the jawbone Up3 for about a week and a half now. It's comfortable and the battery lasts a long time. The step calculator seems pretty good and the sleep review thing is pretty cool. However, it does not use the bodymedia multi-sensor calorie counting approach. The stupid thing uses the same algorithms based on height, weight, age that everyone else does. Also, the heart rate measurement is only your average resting heart rate/day + your heart rate when sleeping. Seems kind of stupid. There is talk of opening up continuous monitoring at some point in the future but I'm more interested in changing the calorie count method. it's find for day to day stuff, but when you're busting your ### doing non-exercise work like gardening, snow shoveling, etc, it's no where near as accurate as the bugg.
I think I'm going to be keeping since I already have the bugg and I have hope for this thing for the future.