I'd take a Glock 20 with its 15 round mag any day over a .357 with 6 or maybe 7 rounds. Heck, I'd take the G20 over even a .44 mag. In a bear charge I wouldn't trust myself to be as accurate as I am at the range, and the greater capacity and faster follow-up shots of the Glock would trump the greater power of the .44 mag for me. Unless, of course, we're dealing with something bigger and meaner than a black bear; in that case I'd want all the power I could get.
0331: "Accuracy by volume."