If I could have only one gun to carry it would be a Glock 19. IMO, Glocks are ugly and utterly reliable. Plus, since the safety is "built in" to the trigger there is no fumbling around at that time when fumbling around can mean life or the rendering of yourself into a permanent non-breathing state. But, that's only my opinion (about the Glock . . . I am sure about the non-breathing thing).
You are what you write.