Sonic 3D Blast is better than Sonic 360 on every level imaginable. It's not even comparable.
Sonic 3D Blast has better music, doesn't have any loading(Except for the Saturn version which...did have awful loading =X), has color(ohnoes!), doesn't rely on shitty friends, doesn't have any angst, doesn't make you ride in shitty machines, doesn't make you deal with bad camera, has better visuals(Looks nicer to me=P),has better play control....and it's more fun, too. No comparison.
Plus, 3D Blast had awesome music and special stages, on the Saturn version.
Now, that's not to say Sonic 3D Blast isn't a boring peice of crap. Cuz it is. Before Sonic Heroes came out, Sonic 3D Blast was the king of bad Sonic games.
But Sonic 360 makes Sonic 3D Blast look like friggin' Super Mario Bros. 3.