I used to be a 1911 fan boy, Gunsite, Weaver and all that. I guess, in many ways, I still am, actually. My transition occurred while attending some training classes. We were presented with problems that were more easily solved with less reloads, therefore higher capacity. On one class we were using airsoft for FoF and I was using a Glock replica. Afterwards I thought, "Hmm... I could get used to this." Yes, I came to Glocks because of airsoft.
I also found I was tending to shoot low with my 1911's under stress and was switching to arched mainspring housings. It has to do with your stance. More upright shooters do better with 1911 grip angles. More aggressive forward posture shooters do better with Glock grip angles. At the range target shooting I was fine with 1911's. Under stress I was tending to lean forward and push into the gun causing the muzzle to go down. The Glock grip angle accommodates this. Now, I think I can shoot either.
You are correct, stance, posture have a great deal to do with it. Grip also grip amgle. I observed a friend of mine, (likes his Glocks). Bring his Glock.up on target, then let him do it with various 1911's, Gold Cups, Bomar Sights, Smith N frame rear sights. RIA BBR 3.10, His approach was the same as the Glock, so in reality his stance, posture, grip was almost the same, this even carried over to a Ruger Single action revolver. More like a "one size fits all approach "
In some cases he caught himself compensating for the differences, more or less didn't feel natural.
I get it mag capacity and all of that. With the way the threats are nowadays, multiple bad guys, groups of them, their spread out, coming at you from different directions,, body armor, etc.
So the number of rounds, before a mag reload is very important. Then you have weight, a bar of lead or a bar of aluminum. A 45 with 14-16 rounds has some weight to it. Vs. Poly gun with 20rds. Shooting the Para Warthog with 14 rds is some weight, vs a Hellcat 15-20rds, Sig 365 15-20rds, XD 20rds.Most people who have held the BBR 3.10 45, their first comment it's heavy (empty) and where do I put my remaining fingers, loaded with ball ammo, its too heavy. I tend to over compensate cause of the weight and sometimes the size ( have big hands ) with the Hellcat, 365, XD, but oddly not that much with the HK USP's
I'm no instructor by no means, waa a NRA pistol instructor but that was some years ago, and don't know it all. As far as Glocks I guess I could get used to them have a Gen 1 ( when they first were available), but would have to change a lot of things. Instinct.. but what ever feels comfortable and you do well with, at the end of the day that's all that matters.
-Snoopz