I've been using a Fitbit for about a week and LOVE it!!! I was a bit worried at first that it wouldn't be worth $99, but (so far) it's been totally worth it, very fun and motivating! It doesn't interfere with my pump at all (I don't wear a CGM), as it transmits data only when it's near the computer. I also use the Garmin sports watches that do the same (a heart rate monitor and swim watch), and they have never interfered - and are also very motivating! Shame that all this stuff couldn't be integrated onto one website, that would be pretty awesome.