>1911
Don't buy Kimber.
High-end 1911s have a "break-in" period where the tightly-fitted parts do not work together very well and will cause malfunctions until the parts wear themselves into proper working order. There is no set amount of rounds to fire before it's "broken in" and, if you're lucky, you might not have to at all.
Low-end 1911s rattle because of the loose fitting - this allows the gun to work more freely without a "break-in" period but the results make it out to be less of a scalpel and more of a handsaw.
GI sights are terrible for anything but aesthetics - actually using them to shoot will make you think the gun's inaccurate unless you practice enough to ignore the suck.
You don't want military issue 1911s, especially if you want to start changing barrels around. The gun has been worn out and will not agree with modern parts.
Don't buy Kimber.