Thats what I have the G23. Love it. You can argue to the death between the .40 and th .45 being the better self defense round. Its a matter of placement, is what it all boils down to.
.45 is a slower heavier, but bigger round.
.40 is lighter, faster, and carries more velocity.
Both great for knockdown.
Its a Ford vs Chevy debate.
Personally, I think the .40 is the better of the two, but whatever you feel more comfortable shooting, pick that one.
CANADIANS = DOUCHERS