Lot depends on whether it is for periodic whacking varmits (or) for self-defense carry. Go with the best for SD carry.
I have a S&W M&P 9mm for summer carry (easier to conceal) and a Baretta .40 for cool/cold weather carry. The Baretta is full size 96FS (the 9 mm equiv. is 92FS) both have same frame size.
My 9mm is a compact. Compacts require a much more secure grip than the full size frames. In the S-A due to weight and "leverage" of the barrel for cycling. "Limp wristing" of the 9mm, .40 or .45 will cause the handgun to jam (failure to eject).
Other excellent choices are the H&K, Springfield Arms, Walther, Para Ordnance, etc. If you like the profile of the "1911" frames (a variety of manufactures have this option), those are other good choices.
Caveat: I'd avoid anything cheaper than $500 new as well as buying any used or pawn shop gun.
If you're very alert and safety conscious, you can't go wrong with a Glock. However, Glocks have little room for carelessness or shooter error...no external safety...only the "trigger safety" (which is an oxymoron, IMO)...lol.
As far as SD ammo is concerned, I use the Hornady Critical Defense ammo...expensive, but extremely reliable and all. All things considered, you get what you pay for in ammo or handguns...
:cowboy: