I too have both. A Steyr M40 and a 1911. I find no noticible dfference in recoil with either. The Steyr holds 12 rounds, the 1911, 8. But if I were to need more than 8 rounds, I'm in serious trouble anyway.
But from experience in shooting those bowling pins shoots and see the pins (especially toward the end of the match) wobble a little from the 40 or the 357 SIG but see the same ones fly off the table with a .45 ACP is proof enough that the old 45 has a substantially more "OOMPH" factor at impact. That frontal mass is what gives the 45 is lethality. You don't get much penetration, but then again, you don't need it. I'd rather have 4 - 6" of penetration and the would-be attacker on his a$$ than a complete pass thru and still coming.