I have a 10.5 pound 577, although it is currently for sale, and I would recommend you get a 13 pound 577. That is the tried and true weight for recoil.

My rifle is a punishment of the first order although a much easier rifle to carry. That is why I got it so light, figuring on carrying it many more miles than times shooting it. Once yu have the load worked up for the light rifle than put it away until it is time to hunt. You will build yourself a flinch if you don't and will not get used to the recoil as it is in excess of 105 ft/lbs.

A 460 WB is less recoil but much sharper. I'm not sure which is worse. Perhaps just being run over by a Buffalo would be easier.