I doubt my post helps a whole lot, but it is my nugget of experience.
.500 S&W Magnum from the big 8 3/8" X-frame, as designed with the OEM recoil reducing grips and the fantastic porting on the muzzle end? It's a rush, and a whole heap of fun. It certainly packs a wallop on the hands, but it is not what I call a horrendous, awful experience. Felt recoil is different for each person, but I find the big X-frame .500 to be more enjoyable than most all .44 Magnum revolvers I've shot. I am being completely honest here. Part of this is because you know what's going to happen and you will typically only shoot a handful of rounds in any session simply because of the economics of it.
However, I sent 5 rounds down range through a T/C Encore Pro Hunter with the Katahdin .500 Magnum barrel and it was a horrendous and awful experience. It was a tremendous recoil wallop that was not enjoyable in any way whatsoever. The first shot sucked out loud and every shot afterward was worse. I see no earthly reason to ever put myself through that ever again and to own a long gun that shoots the round is something that I don't think I'd ever get sucked in to. Of course, I'm not a hunter of any sort and I don't chase African game, so it doesn't appear on my radar.
I can only suggest you find some way (no idea how?!) to get a couple shots out of one before you throw down a couple thousand dollars.