i'm betting on Prime. Vader is likely to sell out his true feelings (whatever they are at the time) or at the very least totally freak out and start choking his large breasted baby-carrying wife, at which time Prime totally shanks his black ass and then says something quite noble about how "darkness is averted yet again, but we may not yet rest..." and then Cybertron 2498 looms in the distance with Megatron doing the drunken Gary Busey laugh like usual.
fuck i'm hard now.