TexasCHLforum.com

No idea about the other one, but you can't really go wrong with a Glock or M&P as far as reliability is concerned. I trust them equally, but I'm also pretty anal about keeping my guns cleaned, lubed, and fed with quality ammo.

My primary carry gun is a Gen4 Glock 19, which is the 9mm version of the 23. It's been fantastic to me. Not a single hiccup in 600 rounds of various types of ammo. My light carry gun is a 9mm M&P Shield. Not a single hiccup in 400 rounds of various ammo.

I know that these aren't the specific guns that you're looking at, but I would have full confidence in buying other guns in these two families. A friend of mine carries the Glock 23 and a .45 M&P, and has had the same positive experience.

Get yourself some range time and pick the one that feels better to you. They're both excellent choices.