I have the original genesis(came with altered beast) and the original CD
system.
I just got Road Rash CD last weekend and it works fine. I have the new
Genesis, new Sega CD and the 32X and it works.
By the way, it's a great game. The first level is too easy but level two
gets harder. And the music is great. You can adjust the volume on the
music, sound effects and engine level.
Brian