Of all the versions of Alien 3, I think the Genesis one is the best to play. The SNES version was one of the first games I ever owned for that console. (After Killer Instinct, Mario, Super Metroid, and I think Super Star Wars.) I loved it as a kid. A few years ago I picked up a Genesis Model 3 and a few games. One of my first grabs was Alien 3. I gotta say it's challenging, and though I abhor time limits in games, it kinda works for Alien 3. The game has a pretty good flow.
Oh yeah, one sorta silly bit of trivia, but I think the sound of the aliens exploding in Alien 3 on Genesis is actually a distorted sample of the scene in Aliens where Hicks shoves the shotgun in the aliens mouth.