Anyway,
Since the man mentioned he was going to get a Glock, here are a couple things to consider as it relates to the Glock specifically.
The Glock was designed to shoot 9mm ammo. Many adjustments have been made to the base gun design to handle the bigger calibers, additional pins to the locking block and frame, stuff like that.
The one adjustment that has bugged me is the redesign, or throating, of the barrel in the 40 cal guns. To keep the edge of the truncated bullet from sticking to the feed ramp, they went in and incresed the angle of the ramp, so the gullet wouldnt hang. Then of course, this lead to the unsupported chamber we all have heard about and the blow ups. Supposedly the ammo makers strengthened the web of the case on the ammo and all was solved, as shooting the cartridge one time would not stress the case enough to blow out.
Then again, we reload and shoot lots of reloads as well, which glock says is a no no. Not going to get into that debate here.
Also, if you look at the barrel hood on the 40 cal Glocks you will see a little shiny spot starting to wear and somewhat bevel where the hood hits the slide. This is accelerating the wear and loose breach will develop faster than with the 9mm guns.
Also, I have seen a few trigger springs break in the 40 and 357 sig guns.
I have also seen 9mm Glocks with over 100k rounds through them and still going strong.
So, I dont think you could go wrong with the model 19.
Just wanted to add a different perspective. Good Luck.