They seem cool for someone who wants a factory ammo capable option with minimal recoil, max barrel life, and sufficient ballistics to get out to reasonable distances. I'd just be hard pressed to choose one over a 6 BR/Dasher if the intention is to shoot nearly all handloads. Wouldn't need a one off bolt face to work with a BR based cartridge either.
It seems like the guys wanting to push the heavy bullets in a 6 ARC often lean heavily on non-temp stable ball powder to get there. A modest load of varget/h4895 or similar in a BR based case to get the same performance sounds more desirable than having to push on it.