Not as good as SSX 3, but still worth it.
The feeling of speed, in this game, is incredible, blurring the edges was a nice touch. Kind of along the same lines as when you use turbo on Burnout Revenge The only real gripe I have with the game is that, in the previous games there was banter between your character and others on the track. I liked being able to pick a character with all his/her enemies and freinds and kind of enjoy the banter between them; crazy comments while going down the track. With On Tour, all you hear is the music, the sound effects (which are really good), and a surpised voice if you happen to run into a "pedestrian" ("Hey", "Crazy snowboarder", etc).
The sound effects are good, complete witht eh wind in your ears when you are going fast. The music fades a bit and the sound of wind in your ears gets louder the faster you go, I play the game with surround sound and it's really cool.
This is definatley a fun game, hard at times (closer to the end it gets really hard), and it will keep you busy for a while.