I find myself agreeing with Shawn D.
Nothing wrong with your 1911, but if you are dead set on using Glasers or Magsafes, I think a .357 magnum is a better way to go. You will not have any reliability concerns because of ammo selection.
But, if you are going to take a bath on a trade, or can't afford another gun (been there) and you have to use the 1911, I think you should abandon the frangibles. You'll go broke trying buy even 100 rounds of these specialty rounds to test for reliabilty.
I would probably consider Triton's Quickshoks. These are not some super-velocity frangible that has a low point of aim, and poor accuracy. (Accuracy may not matter that much at the distances you are talking about - but then again, it may.) When I fired Glasers and Magsafes from my Python, I was flabbergasted at the "spread" of the rounds.
The Triton's will probably penetrate wall board just as much as a JHP round, but will also be less likely to punch a whole out the other side. They are affordable, and function in your gun just like a JHP would - because that is what they are, basically. You seem to be partial to the lighter rounds, and I sympathize. Still, I like heavier rounds that will get in all the way. What if he's 7'1" and 310 lbs of muscle? Now I don't know why Shaq is breaking in to your house, and not practicing his free throws, but you're going to wish you had something that can punch through all that muscle and put him down if he does. I'll shut up about this now.
I lived in apts for years, and just loaded up my guns with medium wt. hollow-points. I used Remington 185gr +ps in my .45, and 175gr Winchester Silvertips in my 10mms. Just make sure you hit him if the time ever comes.
Tom
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Don't Tread on Me
Why 10mm beats .45 ACP . . .
www.greent.com/40Page/ammo/10/10mm-advoc.htm