Decent
Doesn't bring anything new, but it's a good flash overall. It lagged a bit, but maybe my computer just sucks.
The music loop is a little annoying, due to the sudden transition, but the music itself is kinda funny
You should add some kind of GAME OVER thing for when you die.
The game is really easy to beat by just mashing left and right, and the collision areas are too big.
I noticed you had a little bonus stage or something, when it ended (after 60 seconds, kinda long for a bonus stage) I had 3 sonics again, having lost one already. Dunno if it was meant to do that, I'm just pointing it out. Maybe it was meant to do that and I'm just picking nits.