For me, I'd choose a gun intended for defense against badguys that had a bit of capacity. A Glock 19 or 23 carried IWB along with two more mags on the belt would be a very good choice. Impervious to weather, easy to carry, etc.
Five shots in a short barreled gun thats hard to shoot accurately and fast and that's slow to reload wouldn't be MY top choice for personal defense against multiple badguys in a remote location by a long shot.
I don't ever consider a concealable .357 magnum revolver, especially of the quality of the SP101, to ever be a poor choice for defense, not if you know how to use it. If you don't, stay home. I'd never carry a Glock. JM bias, though. And, .357 is a better caliber fired out of 3" or longer barrel with the proper load. Besides, though, the handgun is to fight your way back to your rifle, right?
Bottom line, though, I never feel inadequately armed with a 5 shot revolver, especially in .357 magnum caliber. If you're not seeking cover and you're taking on 20 armed bad guys, you're a dead man, anyway, if you're in the open at close range, unless maybe you are carrying an M60 or at least an MP5. Probably dead anyway, but the full auto fire might scare 'em enough for you to win.
Cover, tactics, tactical order, that's how you fight against multiple attackers.