I'm certainly no expert, but my personal belief is that there's not much a 1911 in .45 ACP can't handle. For example, in your 20-30 bad guy scenario, suppose you drop 1 or 2 of those bad guys with well-placed shots to the brain pan or center mass? The bad guys will turn tail and run. I understand you cannot count on such an outcome, but it's been shown to be the case with these commie agitators time-and-time again. I also prefer the increased terminal performance of the larger caliber. My concern with a high capacity smaller caliber pistol is both the reduced performance and the increased difficulty of keeping track of round count.

l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right.
- Del Gue