That depends on what you want to do. I had the Charge HR and was please except the band started to release from the face area on two consecutive trackers, so I upgraded and got the Blaze. My Blaze battery has lasted longer than the Charge. The Blaze also has some interactive workouts right on the tracker, like 10 minute abs and warm up. So if you have a few minutes you can get in a quick workout. The Charge was my first tracker, but if the Blaze had been out when I first purchased, I would have got it.