The PS2 gets the job done nicely, but without online access to download new songs or even upload the ones you make, it nearly defeats the purpose of the Music Studio and your multiplayer is limited to local head-to-head and four-player co-op.
Guitar Hero: World Tour has a few kinks to work out, just as the first Rock Band did last year. But it's still a worthy contender of Harmonix's new offspring and is also worthy of being added to your game collection.
Do you like Guitar Hero's tracklist more, or Rock Band 2's? My personal choice is Guitar Hero: World Tour, as its louder and heavier soundtrack puts a bigger smile on my face than Rock Band 2's unusual mix.