I think you should ask in the General Firearms Discussion forum, but I'm here at the moment so this is what I think: First, a lot depends on the weight of the rifle, the recoil pad, and the way it fits you. Comparative recoil forces can be found on the web, but are only useful in general terms. Personally, the 257 Wby. that Ive shot was a pussycat. I'm currently using a 25-06 with a long bbl. on a Ruger #1B and getting better velocities than those pubblished for the 257 Wby. with a 24" bbl. and it's about as easy and comfortable as can be.
Either cartridge is perfectly adequate for moose and elk if you hit them in the right place, and of course that's true for any rifle/cartridge.
If it's a good buy get it. If for any reason you decide you don't like it just sell it and try again, and there's always a market for weatherbys. It will be expensive to buy factory ammo, but if you can start handloading the cost goes way down.
What he said.