The Ratchet and Clank legacy continues. You don't see a game specifically made for the PSP format only. You can tell this was made from the ground up and they used their knowledge of the platform to build an awesome game.
There are so many aspects to this game, so many different games within the game that you can't begin to describe them all. The puzzles are a lot of fun and really, there are so many save areas that you will get through this game without the frustration of having to play your past 30 minutes all over again just because you walked off a ledge.
The sound and voice are well acted and very humerous -- even to the point where you feel like you want to complete the level to sit back and watch what will happen next.
A definite buy game which has all of the aspects you are looking for in a game.