I'd prefer what I shoot best but thats not allowed on this post!
The pistol I shoot best is an old Dan Wesson .44 mag, after that probably my old .357 Blackhawk, then my .22 Ruger target pistol and none of those would be allowed on this post, or in the case of the target .22, not a 'harms way' type weapon. I know revolvers don't qualify here, but I really-really like that old Dan Wesson.
So what I carry is usually a Glock model 30 or a Glock model 23. I probably shoot the .45 model 30 a bit better than the 23.
My wife on the other hand just about only carries a Glock 30 even though she has other guns. She has a lot of confidence in a .45 and is pretty particular about her carry ammo for defence.