The Shadow and Sonic levels are really good and the story is good cheesy fun. Unfortunately, that is 1/3 of the game. Not only did they bring back Omega and Knuckles' gameplay styles, which were... alright, back in SA1, but they took steps to actively make them worse. Eggman/Tails are much more sluggish than Omega, and the radar only showing one of three objectives at once is so, so annoying. I understand making a game with only Sonic gameplay was very difficult at the time cause he goes through levels so fast, but regardless the solution is just... not good.