I've had the opportunity to shoot a couple of Glocks with the Robar reduction. The pistols pointed like 1911's, improves gripping considerably, and the process iis professionally accomplished. That being said: I wouldn't do it on the Glock medium sized pistol unless I was trying to accommadate really small hands. The difference in grip size is not that great. An unmodified Glock does point a little higher compared to a 1911 grip angle and I shoot mostly 1911. It takes very litttle time to transition to the Glock grip angle.
I would have the Robar reduction done on either the 20 or 21 though. I have small hands and in mine, I find the Glock large frame dosen't allow a proper grip. I just stick with a 1911 when I want to shoot 45 acp.
