Congrats on the Gold Cup. You made a great choice. I have a lot of respect for Colts, especially ones that have visited their Custom Shop.
I was about to chime in on the STI's. Nice pistols, but I do not view them as highly reliable based on my experience in USPSA competition. Nearly every match, one or two would break...extractors, sights, firing pins, etc. Granted these were high use race guns, but I've used Colts, Springfields, and Para Ords for years and years with out mechanical problems in matches.