Nothing wrong with a 300wsm. I almost bought one because WSS had $600 Thompson Ventures on half price... They sold out before payday though...
If I way to pick, I would be tempted to go with the regular 300wm over the short mag though. Yeah, you get a shorter, handier rifle with the WSM, but you don't really get the magnum performance from the WSM with the heavy 30cal pills, which is what I would want to be using in a 300mag (200s specifically)...
If you wanna shoot 180gr faster, or go with a 150gr TSX at ludicrous velocity, then the wsm is a great choice. If you want to be able to throw more weight than your 30-06, then the regular win mag is the better option IMO.