With only a few minor setbacks, Sonic Rush Adventure is a game that's definately worth renting, if not buying.
Gameplay: (9/10) The gameplay is really fun- all the same classic gameplay like in the previous Sonic games are there (ex. loops and rails and such), plus new add-ons (the gliders in the metal world, the mine carts in Coral Cave, etc.). The problem here is when the game gets repetitive- you have to go to islands again and again to gather materials for Tails, and you have to play the same vehicle minigames over and over to explore new islands.
Graphics: (9.5/10) When comparing Sonic Rush with Sonic Rush Adventure, graphics pass with flying colors on Sonic Rush Adventure- 2-D and 3-D graphics are mixed in right where they should be, and it gives the game a nice feel. I also really liked how there were 3-D bosses when any game producer could have made it 2-D, and the mixed in 3-D graphics during game levels were something beyond expectation.
Controls: (9/10) For the simple tasks, such as moving, jumping, and dashing, the controls are excellent; when you want to show off your tricks to fill up your dash meter however, it becomes a little more tricky but sadly vital for goal time missions.
Replayability: (9.5/10) Yes, the levels will get repetitive if you play again obviously, but it's still fun in its own unique way. You also have the 100 missions to beat, extra islands to explore, emeralds to gather, and the Wi-Fi connection ability to go against others (I can't rate the Wi-Fi at this moment since I've only beat the game and played the missions- I haven't gotten to the Wi-Fi part yet).
Music: (9/10) The music is catchy and is actually bareable to listen to- I personally would give music 10/10 if it wasn't for the fact that the voices for Sonic, Tails and Blaze sounded awful and I was disappointed when the music in the sound test wasn't the exact same for the actual music played in the levels (compare the music from the sound test and the actual music played in the level and try to listen for sounds in the background- it's kind of hard to explain).
OVERALL: (9.2/10) Sonic Rush Adventure is a really good Sonic game- go out and buy it, even if you aren't a Sonic fan, then just rent it for Pete's sake. The game is just right- not too easy or hard, music is bareable, controls are not too simple but not too difficult, and there are many fun features besides the storyline to play though. Besides the few problems I described above, this is a really good game.