If I was doing a dedicated Buffalo rifle I would go as close to a Mauser as I could or a M70. I think I have actually had more jambs with controlled round feed but hard to say, it is just the classic dangerous game rifle. I would go British Express or American Classic in style. For those that they fit the Weatherby does do well with recoil but not for me.
If you have rounded shoulders and a long neck then the California style may be for you. It also fits many women well but for me it increases cheek slap and muzzle rise.
Many PHs use push feed rifles of various sorts and even as a dangerous game back up rifle so I would go with what you prefer. I wouldn't worry about mixing a push and controlled feed rifle as a pair but I would like the same type safety on each preferably a three position one. Also the Mauser, Winchester, Dakota style of open trigger would be my first choice as they are almost fool proof.
As far as cartridges I would be torn between the 375 H&H, 404 Jeffrey and 416 Rigby. All of them are good, the action size and weight of the rifle would make the final choice clear.
