With this thread inevitably headed for a popularity contest of personal favorites I will say if one considers all facets, the 357 Magnum is a hands down winner.
1. Excellent power for both SD, and most hunting.
2. Easier availability of common comercial ammunition.
3. Smaller size weapons available for CCW, and lighter weight for extended carry in the woods.
4. Lower cost of commercial ammunition. Including much lower cost for 38 spcl as practice ammo.
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!