The 6.5 does have the best SD in the 140gr pills and likely the least recoil, but with a 7-08 he can step up to the 168 berger with a SD of .316 and be shooting a much heavier pill since he mentioned he may shoot this gun as well and was asking 7-08 vs 308. I will say the 168s ran about 2700 out of my 7-08, but recoil was sharp. Definitely not a paper punching combo in a 7lb gun.
Bottom line is that a 6.5 Creed, 260 Rem, 7-08, 308 all have ballistics so similar, no animal hit with them will ever know!