A while back I picked up two Colt CCO..Concealed Carry Officers models. Thats the commander 4 1/4'' barrel on the officers frame. One was the XS version and one was the MK IV series 80. I don't like front slide serrations and ambi safties so I sold the XS and went to work on the MK IV. The first change was to put in a Comminillo full leangth guide rod, tossed the el cheapo trigger for an adjustable one and next a Wilson drop-in barrel bushing and then a set of XS SightSystems Big Dot nightsights. The pistol always shot well but man the planets must have lined up on this one because it does it all. I know this is not everyones cup of tea but it sure is keeper for me...........