I had more than one person at gunshops tell me, and from handling enough I guess they're right, that pretty much there's most guns which have the 1911 grip angle, and then there's Glock which is a steeper grip angle.. He put it this way.. "With the XD's, M&P's, etc.. you can grab a 1911 and still be used to the angle, but once you're used to a Glock, you're a Glock shooter, because it's different entirely." He pointed to the XD which he stated was most like the feel of a 1911 that could be had from a poly pistol.
Disclaimer 1: Not saying if that's true or not, just what I've been told.
Disclaimer 2: I'm a total newb learning about the different brands/models myself.. so I'm no expert.