Yeah, its graphics were good (although they suffered a bit of slowdown in the PAL version), but it was just too easy and you could complete A LOT of stages in a few seconds. In fact, it was one of my Christmas presents and I found it inside my mother's closet two days before :
: and completed it that afternoon, hehe.
Bonus stages were also decent, they were the only difficult task to complete in the game and their variety was interesting. However, SMS/GG Sonic 1 had the best bonus stages, and they were much better than that rotating stage found in Genesis Sonic 1.