Greetings,
I bought a VV Encore rifle barrel in 500 S&W several years ago. When I first shot it the recoil was so severe I immediately sent it back for a muzzle brake. When I shot it with the muzzle brake it was still too severe for me to enjoy at all. Mind you: I'm not a complete wuss when it comes to recoil, as I can stand full up 45-70 loads with no muzzle brake.
I first loaded Hornady 350 XTP bullets. I shot a deer and while the deer immediately went down, the bullet completely fragmented with little penetration. I suspect the bullet was made for pistol velocities, not rife velocities. I then switched to a Barnes 275 bullet. This too was still too much recoil, so I eventually sold off the barrel.
I'd recommend you go for the 460 S&W barrel, because you can download it with 454 Casull and 45 Long Colt rounds. I think there are now 500 S&W Special loadings out there, but I'd still go with the 460.
Good luck, and have someone take a picture of you firing your first shot with this rifle.
B. Noz.