Super Street Fighter II: The New Challengers (both OCS and AGA versions) aren't too bad. The gameplay is perfect, the sound is good enough too. Shame about the graphics, they look worse than the original.
Hey, at least Golden Axe got an awesome Amiga port!
Apart from Afterburner and Teenage Mutant Ninja/Hero Turtles, Amiga didn't get too many different versions of the same game. TMNT/TMHT is interesting though, we got the US TMNT version here in Australia, when I found out the UK version was a totally different port of the same game I was intrigued, the UK version played worse but had much nicer pixel art. I still like both versions more than the NES original though.