I never finished this game as a kid, and now i remember why. It has a very inconsistent difficulty curve, being crazy ass difficult in some levels and really easy at others, same thing for the bosses. Jumping in this game can (and will) be really frustrating, especially when you can't hit the double jump.

I know games had to be design like this so people would stay playing, but without save states i think this is too hard to be fun.