It's really a matter of opinion. I'm a big guy 6'3 220 and I can shoot an 11 lbs 470 OK. I can't hit a barn and elephant is slightly smaller then a barn with a 577. The only 500 I shot was a BP express so not much there.

So far I prefer the 450\400 3 (or3 1\4) for precission and recoil confort, that rifle weighed around 10lbs. It was a pleasure to shoot and I could put 4 inch groups 3r 3l at 100 yards. At 50 the group was closer to 2 iches.

Gun fit, a good recoil pad and don't shoot of the bench until you get comfortable with your cannon.

PS. What about those recoil mercury reduction thing amabobs?