Over the last 35 years, I've carried revolvers from a .38 Airweight snubbie up to a 6" .357 N-frame, and semis from PPK/S to 1911s - and some pretty awful BUGs, as well. HATED Glocks, until I decided to get a poly carry gun. Tried G17, G19, M&Ps, XDs (pretty much all the rentals) and wasn't inpressed by any until the rangemaster suggested a G30. Loved the way it handled and the outstanding accuracy. Bought one. Wanted a 9mm range gun, same guy pointed me at a G34. It took me 300 rounds or so to quit trying to shoot it like a 1911, changed grip and got it hitting where I wanted. Now my carry rotation (we only get three on a CCW here) consists of a G30, a G36, and a G26. I also own a 17L, a 21, a 21SF, and am waiting on a 19. Just got a Advantage Arms .22LR conversion for the 17L/34.
I now own more Glocks than any other brand, and shoot them nearly exclusively. The longslides (17L and 34) need sufficiently powerful ammo to function (PMC Bronze will short-cycle them on occasion) but I could change RSAs and cure that. The rest shoot anything and everything. I have yet to get one dirty enough to cause a malfunction - but I'm sure trying!
If I had to pick up a NIB pistol and defend my life with it immediately, my first choice would be a Glock.