I haven't considered the Rowland due to the required porting modifications involved, but I have considered having one of my 1911's set up to shoot the .45 Super round.
I know some folks claim you can just do a recoil spring swap, but I suspect you'll beat your gun up in pretty short order if that's the only provision you make for the additional forces being generated.
To be honest, I haven't done anything thus far because the 100 fps velocity advantage offered by the .45 Super over a decent +P load isn't likely to be a game changer on anything I'm likely to shoot.