Personally, I would make him a regular human type character in the sense of damage. He mainly takes SDC based damage as MDC implies he is not really affected by normal items. He is actually affected, just momentarily.
I’m not sure how you intend to integrate him into the game, whether you want to allow him to be destroyed or not, but I would give him a high MDC rating with an automatic regeneration rate, somether ewhere he could heal almost immediately even if blown into little chunks. Remember the episode “Terminal”?