I'm in for either. Like many have mentioned, a stout load, and a well placed shot or shots, and a damned lot of luck is your only hope with .357 or 10mm and a bear..
For me I'd use either my 10mm SA OMEGA, or my .357 Mag COONAN. Both are extremely accurate, reliable, and handle stout loads pushing some incredible ballistics numbers.
I figure if I were faced with a charging bear, with either pistol I'd shoot'em in the eye (maybe both eyes if I'm lucky) at 30 paces or so.. lol