They are very different even if they are scoring games. I'm a fan of both.
Solipskier is pretty cool, for once, we don't control the main character: we draw the track. The only thing that I dislike in the game is when you loose the headphones, I love the music xO 9/10
Epic Coaster is less original, but the game is nicely done and get all the achievements take a "long" time if you don't cheat. The perfect jump system add more fun in the game. 8.5/10