I think a toss up between the Colt and Springfield Armory. Both shoot pretty well even in the base model. Some folks don't like the slightly squared grip on the SA, but I think thats a personal preference. I do see what appears to be a mismatch on the SA's on their mainspring housing to frame fit, but have shot enough of them to know it doesn't affect function. SA's and Colts in North Texas run about the same price, and both seem to be cheaper at the gunshows than the Kimber.
The Kimber does have a nicer finish if that matters, as a general rule. I think where Kimber and SA have it over Colt is that they offer upgraded models which gradually escalate in price.
Colt doesn't seem to want to offer much but a base model, then jump to their premium model which is really close to the Gold Cup price-also not a bad buy these days, but its pushing a grand really hard!
All of them can get rid of the "cheese grater" grooves on the front of the slide, IMO. It's no place to put your hand and shouldn't be encouraged, not to mention it looks ugly. Fortunately, Colt and SA doesn't do that on all their models.