Felt recoil is going to depend on how the grips fit you. As others have said, neither should be problematic recoil-wise.
I've fired .45 ACP from 5" 1911s, a 4" 1911, a 4" S&W Mountain Gun (wish I had that one myself now!
) and a S&W M&P45. Of the bunch the M&P kicked the "hardest". A 5" 1911 or the 4" S&W N-frame is a pretty soft-shooting big-bore IMO.