I love this game. My favorite Mario RPG out of all of them (followed by Paper Mario 64), it's so good. It's quite story heavy, which differs quite a bit from most other Mario games, and it really builds off the previous 2 Mario & Luigi games. Returning characters, references, and just being built off of Partners in Time really makes this game work. While you do lose 2 playable characters from the last game, you do gain a new one, that being Bowser. His style of play is much different from Mario and Luigi's, which I think is for the best, as the Baby Bros. from Partners in Time were just Mario and Luigi but slightly smaller with worse stats. But Bowser, he's a powerhouse. While he can never work in tandem with the Bros., he makes up for by being able to crush every enemy in his path. Overall though, Bowser's Inside Story changes quite a bit from the last 2 games, and it is just a lot of fun, with a wonderful world. If you like Mario and RPGs, give this one a shot.