at the moment - if i want to pause a workout or skip a song whilst on my run i have to reach my right arm accross my chest to press the button on the nano armband- the angle makes me loose concentration and speed whilst running.
The watch is easy access and also means i can get rid of the armband and put the nano in a pocket and still do a work out.
I'm also guessing that if i'm in the gym on the treadmill and i want to record my run i can just have the nano without headphones on in a pocket - the watch starts and stops workouts and also tells me what pace and distance i've done.
Mine will be here tues/wed time so i will do a full review if you like