Played the demo. It's... okay. It's not really as great as I expected, to be honest. Classic Sonic is WAY faster than he ever used to be, so it's a little crazy at times. The spindash just isn't itself anymore, since you don't have to stop, rev it up, or even crouch. It's too powerful, you basically can just hold X for a second no matter where you are to get a massive speed boost. Other than those things, though, it's pretty solid. The level design is fantastic compared to other recent games! Even for being the first act of the entire game, it still has multiple paths to take and plenty of different kinds of areas.