Okay, okay, these are 'cartridges', not 'calibers' - got it; you knew what I meant!
Man I wish that the magazine on the Rem 700 Mountain DM had a "halfway in" notch. I'm leaning toward this one in .280 Rem. The Win 70 featherweight (pristine/like new) in 7mm-08 is in fact up for sale in a sale thread of mine right now - haven't bumped it in several days, but it's in there. It's a great candidate, but I think I like the Rem 700 Mountain in .280 as the best all-around choice of both caliber and rifle features. Fairly lightweight, good recoil pad, nice looking, 22" bbl, all-around caliber, Rem quality (some would argue that's a bad thing) & accuracy, and detachable mag keeps you legal but ready when vehicle carrying.
The 550 FS is a dark horse, since I don't actually own it yet, and I *want* it to be my choice, as it's the classiest, but it's a bit on the heavy side, and I dunno if the short 20" bbl can wring out of the 6.5x55 any more than you could get from a 20" .260 rem.
I should mention that I do also have a .30-06 but it's a beautiful NIB T/C Icon Classic, but I want to keep it pristine and unused for the foreseeable future, for some unknown gawd-forsaken reason. Just cannot bear to hunt with this beeyoot.