Not gaining a whole lot....a couple hundred fps, some more recoil, a bit flatter trajectory, and some more foot pounds of energy.
Personally I don't think I will ever own anything larger than the '06 just because I have not found anything it would not take down quickly and cleanly. I have taken everything from brown bear to groundhogs with it with no problems.
Having said that though......if you want it get it. I'm not sure you can have too manyfirearms.