I hope this isn't too late. Let me give my 2 cents and a question.
I have a Kimber Custom, essentially the same as the model your considering except for the adjustable sight. The day before last I was at the range with a friend. He had brought along his dad's stock 80 series Mark IV. Damn, I was impressed big time. Now the Mark IV is a far cry from the quality expected of a Gold Cup 70 series, but its craftsmanship and quality was lightyears above and beyond my new Kimber. The trigger, the hammer, the weight and balance, everything on the Mark IV was superior to my Kimber. If it was my choice, and you could get the colt at $700 (which is quite a deal), it would be the Gold Cup hands down. As a matter of fact, if you get the Colt and don't like it, I'll trade you for the Kimber with a few extra goodies on my end of the deal.
Now, a question to the responders. How many of you actually have enough experience with various 1911's to give sound advice ?
No offense intended, I noticed a few of you mention you shot in matches and probably have a lot of hands on experience with various makes. I am still fairly new, but with added experience Its getting easier to spot when someone is blowing sunshine up your ass and doesn't have a clue what they're talking about. Just curious, someone commented that the Colt 70 series Gold Cups have been crap for the past 15 years. What experience do you have to back up this opinion ? I was under the impression that Colt discontinued the 70 series long before "15 years ago". Maybe your thinking of the Kimber Gold Match.