For me it's a 1911 Colt, but a question you should ask yourself "Do I really want a 45 ??"

I have several Colt 1911's and find myself shooting 9mm's and 38Super way more often than the 45's.
my friends that I shoot with like a 1911 in a 40S&W and a long slide 6" 10mm (Dan Wesson Bruin).