I have the Polar (cs-300 I think) and I like it although the wrist watch is big. I wanted one unit I could use for the bike and the run, and I didn't have a cadence sensor so this seemed like a logical option. Although now that I can actually run, I do wish I had GPS, but I can pretty well estimate the distance based on time.

The HR has been a big help to me. It lets me know I'm jogging too hard. On the bike it's horribly slow (and frustrating sometimes) to keep my HR low, but I know it's what I need to do right now. I don't wear it to swim.

As for the strap, I don't mind the regular HR strap -- I don't even know it's there. (I'm too big to wear one of Polar's bras.)