Tough comparison for me. I currently own a 6.5X284, have owned 7mmRM in the past and it will be the next barrel I purchase, probably first of 2014. Absolutely love the 7Mag and have grown to love the 6.5x284.
Quoting the write up in Nosler's #5 Reloading Guide "Since the mid-1990s, the 6.5-284 has dominated 1000-yard competition. The 1000-yard ballistics of a 140gn 6.5mm bullet at 2900 to 3000fps muzzle velocity equals a .30 caliber 220-grain bullet at 2800 to 2900fps, and you are subjected to half the recoil!" This one quote had a lot to do with me obtaining a rifle in this caliber. No doubt about it, it is a accurate round, with negligible recoil.
The 7Mag, IMO, has just the right combination of power, speed and accuracy. I think with a good rifle and tailored handloads, it can and does hold its own at all ranges. For hunting out to 650yds, either will do/flip a coin. Past that I'd probably lean on the 7Mag because of its power edge.
Better yet, get one of each!