An Air Weight S&W .357 Mag is not something you're likely to fire more than 5 rounds from at the range.
The S&W .44 Magnum w 4" barrel is not something I'm going to be able to get a follow up shot off, on target, in time to stop a charging griz.
I carry, train, and practice with an S&W 686 (357 mag) 7rd w 4" barrel. Using 200gr hardcast rounds when in Griz country.
10mm is reported to be effective as well.