I don't have a 6.5mm-284, but if I reloaded I think it may be the 1st I bought....its a very popular benchrest round.....superbly accurate and being a 6.5mm you could load it across the board up to 160grs or so, and since you said .25-06 and .280AI.....it's right in that range....

If you plan to reload the 280AI anyway....granted you can fireform brass etc...but you're still reloading you may want to look into the 6.5-284. I know its getting more and more popular too and perhaps somenoe will eventually load it.....

I hear ya about wanting 1 of everything....but then again I'd rather have a few awesome rifles vs. a bunch of junk. Going with a Cooper I suspect you're thinking along similar lines....

I just noticedwhen I checked out Cooper's site that theyloaded the 6.5-284 so thats why it caught my eye.

So being inherently accurate and in a quality rifle, I dare say it'll outshoot the other 2, though all 3 would should well I'm sure, and having the variety of 6.5mm bullets.....you could hunt light or heavy....as light as the .25-06 or as heavy as the .280....