Glock KB's are about as much of an issue as slides cracking on Beretta's. improper ammo, or bad care will #### any gun up. Ask how many Sigs I've seen with rails ripped off? Howabout 6 in BC alone? some with high round counts, some with low. My old original Beretta 96 had 160,000+ rounds through it before I finally broke the locking block this past summer. My current 92 Elite II is somewhere in the 40,000 round mark, and my 96 Elite II is somewhere around the same.
I've also seen 5 Glocks that KB'd supposedly with factory ammo (but I have my doubts).
I've also seen factory Winchester ammo with no primer holes (primer pocket yes, but no flash hole)
Do you get the point? modern stuff still screws up, doesn't matter who makes it, someone will have a problem at some point with it.
As for .40 S&W it was an answer for a question that didn't need to be asked, modern 9mm defensive ammo performs almost exactly the same in as far as permanent wound channel and all that. As well when you look at kinetic energy, it's Mass x (Velocity squared), which means a fast moving 9mm will impart more energy to a subject than a slow moving .40 or a slow moving .45 and typically you'll be able to throw more of them at a target. So my money is on 9mm. Of course that doesn't mean I haven't ordered a .45 ......................