These issue, are all solved with the 6.5cm you already have
. Do you realistically plan on shooting at game past 500yds?
If not, the extra 200fps of the PRC isn't going to offer much. Bullet dependent, but say 1900fps as a floor for reliable expansion (more important than energy), will get you to 600yds with the CM. PRC will get closer to 800yds.
If so, then then 6.5prc on up will suit you much better. But this comes with the cost of ammo prices, shorter barrel life, and more to significantly more recoil.
Higher ammo cost and more recoil, almost always means less training rounds fired. More game is lost to poor marksmanship than not enough gun. I don't know how good of a shot you are, but would you be more deadly with a new rifle, or a case of ammo worth of training? If you're already a hell of a rifleman, then shoot whatever you like!