I just had this discussion/argument with my Dad today haha. Flip a coin. Both are ballistically identical. Both have brass from multiple sources. If you already have an action, that makes the decision easier. The PRC works great on a magnum short action with a 2.950"+ Mag box. The 6.5x284 works the best on a standard long action. Both will push the 140 class bullets to 3000+ FPS and 147-156 bullets 2900-3000FPS. If you don't reload, than the PRC is the obvious choice. I think the PRC is here to stay and will continue to grow and be pushed by manufacturers and be supported. Neither choice is a bad one, I think the PRC is the better choice for the future and in the long run.