It's enjoyable, but like everybody says, way too short.
Sonic R isn't like that type of terrible - enjoyable, good multiplayer, but very short. There are only five tracks in the whole game; four if you didn't count the unlockable track. You can unlock characters, but those are just robot versions of the characters you can already play.
Everything is like this: Sonic goes very fast, tails has good turning, knuckles can glide, and all Amy can do is just sit in her car. That means Sonic is better than all of them. It's just not fair.
Graphics are great and the sound is better than the most avarage Tony Hawk Pro Skater 2 songs, but this is defently rushed. Getting Outrun is much more better. But if you eant speedy gameplay, this is one you should buy.