Right now my two carry guns are Para 12.45 and Kahr MK40.
I have had times when I had concern:
1.I went to a public restroom. As I was leaving a "youth" was standing in the doorway with large knife and said "give me your money". I said that I did not have any, which was true. He ran, and let me live. I had no way of protecting myself. I felt so weak. I was not old enough to own a gun.
2. Motorcycle gang blocking a road where I knew a carjacking/assault had occurred about 1 month before by motorcycle gang in rural Florida. I had a Dan Wesson 44 mag in the car...loaded. I floored my car and they scattered, but chased me. I had the gun in my hand when I had to stop behind traffic at a traffic light. They chickened out. Lucky for them.
3 Had my apartment door kicked in by a home invader that probably followed me home from the grocery store because I was driving a Porsche. I heard noise and had a Charter Arms 44 SPL that I was bringng up, just after my door was kicked in, and the home invader stopped charging and ran. I believe his clothing prevented my carpet from being soiled.
4. I was driving home from work when I saw that the car next to me was a car full of "Gang Members" that were tailing an elderly woman in a Mercedes and were motioning like they were targeting her. I had a Glock 30 in the glove compartment and felt confident honking at them and waving my finger. Thet took off weaving through traffic. The woman in the Mercedes never knew anything.
5. Was at an ATM on a sunny Sunday afternoon. As I was finishing the transaction A car pulled up behind me with 5 "youths" with bandannas on their heads. They were in the handicapped space. They were saying "yougeddim, no yougeddim". I grabbed my money and ATM card and made haste back to my car. I had a colt ponylite .380 in my pocket. When I was in my car, the other car peeled out of the parking lot.
Once I had no weapon, twice I had fairly powerful revolvers, twice I had semi-autos. I currently carry a Kahr MK40 if I can't conceal easily and a Para-Ordnance 12.45 LDA when I can conceal. The concealability seems to outweigh the reliability of revolvers. But, if I had my choice I would have my Mossberg 500 with 00B.