Depends on how I feel.
Quick trip out the door, the 640-1 loaded with GDHP (short barrel magnums) on the hip and a reload in my pocket. I shoot this one real good. (My daily on-duty backup gun)
Or, if it's not too hot outside; my Glock 17 (Duty gun). [Hard to beat this firepower when you really need it!] Not to mention the amount of trigger time I got on it.
On rare occasions, I strap on the tuned up Colt 1911 "smoke wagon", and two mags. I am probably walking around with a **** eatin grin on my face when I carry this one. For some reason I just love my Colt.
I recently picked up a 2" Model 10-6. I have been spending some time with it at the range, and for some reason I shoot the wheel guns better than the autos. [Because I slow down and concentrate more] As soon as I get around to it; I will qualify with it as an off-duty gun. Then, it will be my companion on trips around town.
I have spent many hours on the range over the past fifteen years. I am fortunate enough to be in a position that I carry daily, and train frequently; at my departments expense. But for off duty carry; my wheelguns give me the security without making me feel like I am just working in "plain clothes".
Go figure?