Looking into getting the game+Justifier package myself, since at the moment I have only been able to test it out via an Everdrive with an arcade stick.
Still, when compared to the SNES version my comments are:
+ overall plays more like the arcade
+ no censorship - correct stage names, blood / violence etc.
+ additional annimation on all opponenets when they are shot (in the SNES version they just flash and disapear)
+ / - no stage select increases challenge but is a pain when you want to just kill a few minutes on a given stage but instead have to do tchem all in order
- less colour
- less breakable background objects
- inferior sound effects
Overall despite some shortcomings, I still prefer the Mega Drive version.