Hi again!
First of all read the wikipedia page for this game for technical details:http://en.wikipedia.org/wiki/Dynamite_Headdy
I give 8.0/10.00 because this game is very funny, a little bit short but is one of those you want to continue play levels after levels.
The graphic is excellent with wonderful effects that will impressive you for a genesis title.
I think is one of the best platformers and you must have on your collection.
You can download it for wii or it's included in two compilations: gunstar heroes-treasure box for PS2 and Sonic's Sega genesis ultimate collection for XBOX 360.
Have a nice day.
Sty