As hardcast stated, the .300wm will give you heavier bullet weight options. The 7mm mag will give you a little better bullet BC options. Both are excellent for anything on this continent. I would option for the 7mm mag in that Tikka. It's a light rifle and recoil of the .300wm can be a good bit punishing at the bench. Especially if you are going with 200gr or better bullets. I had a bit of weight added to my Model 70 .300wm since I tend to lean towards the heavy side of the bullet spectrum with it. That extra 14 ounces doesn't seem like it would make a difference, and it really doesn't off hand as I don't even notice recoil in the field, but at the bench it made a world of difference. Don't get me wrong, the 7mm mag can be a bit of a brute in bench positions too but it's not as punishing as a heavy weight .300wm.