I think you've got it narrowed down to two excellent pistols. IMO probably the best production manufactured 1911's going, and I wouldn't want to live on the difference between the two manufacturers.
The FBI uses the Springfield Armory. The Marines & the LAPD use the Kimber.
I think you could probably search all day on the forums and the opinion pendulum would swing back and forth. If the cost is comparable, I would probably just go compare them side-by-side again and pick the one that struck me as my favorite.
Then there is always the traditonalist choice of a Colt. I don't think you would regret a Colt purchase either.
Good luck, wish I had your dilemma. Since I don't need adjustment sights, I would probably choose this:
Kimber Tactical Custom II