Wheeeeeee!
Short: Wheeeeeee!
Detail (includes tiny issues I have on semi-close listening):
0:29-0:31 :: I somehow really really really enjoyed that transition. Can't quite figure why.
0:39-0:40 :: My only problem. The background buzz feels kinda choppy, as if it were repeating a pattern that didn't quite fit end to end with itself or something along those lines. This occurs a few times, most notably again at 1:03 and, well, everywhere that it does that. When other stuff was playing, though, I didn't notice it the first cursory listen throughout the song, but afterwards I heard it occurring throughout the song. A suggestion: maybe vary that buzz a little more during those parts, kinda like what you do at (for example) around 0:48-0:55
0:50-0:55 + 1:12-1:18 + etc. :: those little machine noises are just the touches needed to make it feel like a sonic track from the original Sonic Adventure, especially the overworld environment. Subtle yet poignant.
~1:20 :: chillin', man, just chillin' :-)
2:33 :: Probably just a matter of style, but that little right-channel *shoomf* felt like 'too much'. Not really sure.
Overall: I have a love affair with piano sounds. This wins. Also, the little machine noise subtle touch things were *bwaahhhh!!! <3*
Optimistic score + download. :-)