I played a little of the amiga version years ago, i remember it had the same gameplay as most other SOTB games, the punch that you have to time just right to make contact, i do have the genesis version, which has graphics which are very close to the Amiga but not quite as good.
The pce SOTB, definitely has the best gameplay, it is also, from a technical stand point, superior to the genesis version, which might apply to the amiga as well, there are a few exceptions, like the dual layer with the nice tree Bg in the two under ground parts, in the pce SOTB, its replaced with a simple texture, but almost everything else in those two sections are drawn better with more detail. The main character is larger with much better animation, allot of the enemies and bosses are larger, more onscreen colors, more onscreen sprites, better sound fx, line scroll, Bg animations and music.
Allot of the Genesis Bg (Amiga even more so) are stylistically, in my opinion, better, sprites look worse though.
Its interesting to point out that the Megadrive version was changed to look more like the turbo duo/pce version, the main character sprite was redrawn and colored, along with a few enemy/bosses, i don't know if this was done contemporaneously or after some had seen the Turbo duo SOTB.