Pretty good, but it can use some improvement. Try shading a bit, and work on perspective.
Personally, I'm not much much into the Sonic style...It's not very detailed and for someone like me...who is actually literally incapable of drawing simple styles because OCD, it's rather annoying. I much like making my characters look zaidi like furries...
That said, I haven't done much of anything with my characters in...forever...because it passed, and because no one wanted to RP with me most of my characters never got developed past the picture and some of the background...Like Flare here...
