I found that I broke through a couple of the devices- because if you try to attach it to some article of clothing it can break. At the same time the holder they supply is horrible. I have been through three of them in a year - it is very easy to catch the thing on a car door or some other thing you interact with and so I have destroyed four of them (I have also broken two of the devices) - durability would be a plus here.
But all in all the Fitbit is pretty slick. You can compete against others and post to all social media. The newer model also allows you to figure out how many stairs you have climbed in the day. Both models also allow you to track sleep - although I have not used it for that. IN all this is a great product for the money.