Glock 21sf
+famously reliable
+ easy to shoot trigger, quick draw
+durable
+rust resistant
-big and fat, a G22 wouldn be a better CCW
-the SF frame feels even more blocky than the 21 frame, avoid the sf unless you have small hands
-needs a good holster, I suggest crossbreed and Raven concealment
-trigger is made out of wood, rough wood with sand in it.
FNP 45
+reliable, has FN ever made a bad gun?
+seems nicer than an M9 (if you don't mind plastic)
-big and fat
-slow DA first trigger pull, slow to get out of the holster
-harder to train newbs on the DA/SA trigger, especially decock and reholster
I think the Glock is a better choice overall. It offers higher performance, but requires trigger disipline, and some care to reholster. I'd take a long hard look at the G22, 23, 17,16 and fullsize 1911's as well. I wont carry anything larger than a 1911. Both the above pistols are too fat for me.