Retro-Nerd: I agree on Gunhed, you advised me on that one - but that is PC Engine (way off topic!)
TheCyberDruid: The colour use in BS is superior to X2? Don't make me laugh! You have no aesthetic taste - like some of these programmers!
Another thing about X2: BIG power-ups. Another reason I doubt the higher framerate would have been possible back then.
But I would love to be proved wrong, as I have already in this thread.