I’ve used up24, charge 1,2 and my current watch is charge hr 3 for more than a year. Charge hr 3 is my favorite but it’s not perfect. The pros are 5 to 7 day battery life, step tracking, hr esp if your an exercise nut and sleep tracking. The sleep tracking was recently upgraded with oxygen count or something that sounds like that. The feature tracks variances in your breathing while asleep. I found the data quite interesting for example a full meal late at night increases my resting heart rate, no air conditioning also raises heart rate. This ties with my own analysis that my having optimal sleep is tied to a cool environment. That I think is the best feature: when you can try to tie in your own individual life decisions and patterns to how your body reacts to it. I have not tried any of the versa or higher end Fitbit. Hopefully, this year Apple comes out with something better for its own Apple Watch like better battery so sleep tracking can be enabled, only then will I fall to the temptation of getting an Apple Watch.