Let me add another vote for the mid-size model.

I have the 6.5" S&W 500 (standard model) and love it. It has the right balance of weight and pointability, and is plenty accurate. It also fits a belt holster nicely without being too awkward to carry.

RE Bear Spray: This is very useful stuff to have as a non-lethal "go away" spray for dumb animals that you want to deter but not harm. Charging bears need something stiffer I think.