I kind of hate the art, but otherwise it seems good and has nice extra features. I know it is soooooooo nitpicky, but I really dislike how the levels are named. I know that is a weird complaint, but I have always been picky when it comes to the quality of the level names. For instance, an early version of Sonic Unleashed had Spagonia as "Orange Roof Zone", which I thought was brilliant, and extremely mad they changed it into something so bland and generic like Rooftop Run. Bleh.
tl;dr another fan Sonic game better than what Sonic Team can do.