And what is that if you don't mind me asking.
Mike,
A number of things (some of which I'm aware are also available on some other devices such as FitBit, as an example). FWIW, I only have the GPS model, not Cellular+GPS
1. Nice digital watch that I can put an analog face with second hand. (Good)
2. Excellent integration into the Apple ecosystem: ECG, exercise and cardio apps are very good.
3. Good integration with some of my activity apps (not so good on others).
4. Walking navigation via haptic touch is not too bad...taking some time to get used to it.
5. Technological longevity is pretty good. My wife has a version 0, it's still going strong.
6. Very good battery life. Two days before charging.
It doesn't sync well with Strava unfortunately.