My 2 cents...
What Grey-Wolf said in first post...all true.
I have tried the square bottom FPS with almost no radius, it was the best modification I have ever made with the most noticable effect while shooting. All 1911's that I own from now on will have this "old style" FPS. If you tried it, you would never go back.
Far as heavy recoil springs, what comes back has to go forward, just be more stress when it slams home.
My take on recoil springs is use the 16#...and that is probably more than you need, some people like 14 or 15 if they work. It is recommended that a 23# hammer spring and 16# recoil spring work together, along with the small radius FPS.
I don't think you can beat up a 1911 with regular ball ammo made to spec. or any ammo made to normal pressure.
I get a little upset with so many folks using 20# springs and over springing there pistols just to make them function and not looking at the real reason it wont work with a 16# spring.
This is so true....if it does not feed smooth and slick, people want to ram the round home with a 20 pound spring...
sometimes all they need to do is loosen the darn extractor a little bit, or something else simple.