Both are the same age and both in their primes were certified killers. Rogan was dominating on the amateur circuit before calling it quits due to head injuries. Both are legitimate black belts in jui jitsu. In my opinion I’d have to give the edge to Rogan, purely on his physical size advantages. We’ve seen videos of him working out and he’s a beast. Also, I would think being a pupil of Eddie Bravo and his expertise in BJJ would go a long way in taking down Royce.