This is the exact reason I stopped having seven different pistols and started standardizing. It was a nightmare when I went to the range to shoot them, and I think I bent the feed lips on two magazines by putting them in the wrong gun. I've never been a Glock fanboy, but I do like their magazines the best, so I'm in the process of replacing the majority of my pistols with Glock19's.
Imagine if you had several cordless drills, but each were from a different manufacturer, and each took a different battery. That's exactly the frustration felt.