I feel like if I played both halves on their own, I wouldn't like them nearly as much. Though together? Those two parts fit together and create an amazing experience. The levels are pretty, the music is catchy, and the special stages are a lot of fun when you get the hang of them. There's only one thing that I found to be a bit questionable and it was with the level design. Some of the levels feel a lot longer than they should be and some of the zones are really uninteresting, meaning that if you don't like a zone, you're stuck there for a while. This is especially true with Sandopolis, which was a level I hated playing as I already don't like desert level settings that much to begin with. Even so, the game is still great. Sure there were some stages I wasn't a big fan of, but all of the high points are amazing, and there's a lot of highs (Ex: Hydrocity Zone, Launch Base Zone, Lava Reef Zone, etc). Plus, this game has the single best zone in any Classic Sonic game (I love Doomsday Zone to death), though maybe this opinion will change after my Mania replay. Overall, very enjoyable game and lives up to the hype it gets.