I've notice that out of all the Glock chamberings offered the 45GAP, 10mm Auto and 357Sig seem to be the least popular with the GAP leading the way. Granted, a lot probably has to do with the 9x19mm and 45acp being around so long and the 40cal being adopted by so many Law Enforcement Agencies but for some reason the other 3 rounds offered by Glock have only a nitch group of followers. I really love my 45GAP guns and I've had 10mm in both the Glock G20 and G29 and they were pretty good as well. Never had a 357Sig as of yet, my lack of love for the 40cal kind of keeps me from giving one a try because I'm afraid it'll be "same crap, different day" with the Sig round but still, it does intrigue me quite a bit. I just wonder why these rounds never really caught on like I think they should have. Anyone want to venture a reason?