This product fails, almost completely, to do what it's designed to do.
Oh, there are some good points. The OLED touch screen is a revelation compared to Fitbit's crappy monochrome screens. And having onboard GPS and music capability is nice, but since I almost always have a phone with me not terribly important to me. And it does seem to count steps pretty accurately.And..... that's about it.
What does it fail at? Well, it's totally incapable of recognizing a flight of stairs. I live in a typical American home with 8 foot ceilings. I typically go up and down the stairs about 10 times a day. The Pro 2 rarely counts more than 5. Sometimes as few as 2. It even sometimes fails to recognize the 12 foot flight of stairs at my gym. These forums are full of complaints about this problem on all of Samsung's wearables, and Samsung ignores them.
The HR sensor might as well be a random number generator. When exercising, it has no relationship to my actual heart rate. I've compared it to a Polar chest strap monitor, which I've verified by comparing it to my manually taken pulse. On an elliptical trainer, the Pro 2 generally runs 20 to 40 bpm below actual. I've gotten off and had the Gear say my PEAK HR was 20 bpm below what the Polar shows as my average. For whatever reason, though, sometimes the Gear jumps up and shows numbers 30, 40, even 50 bpm higher than actual. It's shown my peak HR at over 190 bpm. I think I'd be dead if that happened.
When weightraining, the Pro 2 varies from about 20 bpm too low to 20 bpm too high, and everywhere in between, at random. Sometimes it goes up when I'm resting and my HR is going down. Sometimes it just seems to get stuck on one number, no matter what my actual HR is doing.
Oh, and it's supposed to automatically go on continuous HR monitoring when I start an exercise program, but that doesn't seem to work either. If I manually take my HR during exercise, it will show a number much closer to actual than the "automatic" reading.
Battery life sucks. I have the HR sensor set to "Frequent," and if I don't go to the gym I can go about 3 1/2 days between charges. But if I spend 90 minutes a day at the gym (with the HR sensor on Continuous during exercise), which is typical, I can barely get 2 days of battery life. My old Charge 2, which had it's own problems, easily went 4 to 5 cays when I went to the gym every day.
And while it's nice that I can see so much information on the watch itself, it does make the UI cumbersome. To start an exercise program, for example, takes something like 7 button presses, taps and swipes to start. Even stopping an exercise takes 3 actions, which seems like at least 1 too many.
I'd fine things like the UI and battery life to be less annoying if the device did what it's supposed to, but it just doesn't. It's no better than (maybe worse), than a $30 fitness band. At $200, it's a complete ripoff.