I've only taken a deer, a black bear, and a coyote (target of opportunity, just happened to be the gun I had in my hands) so that's not much experience compared to a lot of guys here. I haven't been able to get enthused about the 7 mag ( or 7mms in general) had one and got rid of it. Hated to do it too because it was a very nice rifle. Have a 280 I used for several years but I keep it because it shoots quite well and I like the rifle itself. I think the 280 can do anything the 7 mag can despite the ballistic numbers. It is close enough in numbers and performance to the 270/'06/280 that to me it's not much of an upgrade.
Therefore another vote for the 300