Looks like a techno idiot was looking at the 300 yd. velocities
when they came up the MV on the Rem. link.
I read an article in shooting times about the 30 RAR, they compared the 125 gr. RAR loading vs. the 308 Winchester with Remingtons 125 gr. managed recoil load, they were the same, no sh_t. So the RAR is equal to the 308? Not even close. Is it any better than a 6.8?
They pretty much eliminated the chances of wildcatting this cartridge due to the new upper receiver and bolt dimensions. Only if DPMS gets caught up and wants to sell these parts will that ever happen. Maybe they will chamber this in 6mm or 6.5mm or.. and move the shoulder forward, then they will have something.

Its all a marketing ploy to sell more magazines for the gun rags and sell more rifles for Remington. Don't get me wrong here, I wish the gun manufacturers the very best, I'm just not sure why they think that the gun buying public is so naive that they can print such BS and assume we don't know any better.