I'm happy to say that Guitar Hero has successfully transfered to the DS!
Graphics: This is by far one of the best looking games on the DS. Everything animates fluidly, and there's always something going on in the background. The developers obviously kept the graphical limitations in mind while designing this, as they subtly, but cleverly, made the singer the bass guitar player as well. The score multiplier might have been better off as a little icon squeezed somewhere on the top screen however. It can be distracting to try and divert your eyes to the bottom screen while your attention is focused on the top screen. One thing I've noticed though is what happens when you pause and unpause the game: the visuals completely stop moving until the camera change. It's minor though, since the fretboard still works fine.
Sound: The game sounds fantastic, but you'll most likely want headphones. The music isn't anywhere near as loud as you'd probably like it coming from the speakers, even with the volume all the way up. Let's compare it to Elite Beat Agents for a sec. In EBA, you really only need the headphones if your playing it in public, but with GHOT, you may want them on all the time. But judge that for yourself, people say I listen to my music loudly, so it might just be me.
Gameplay: If you know Guitar Hero, you know what to expect. It's just that, minus the Orange Button. The Guitar Grip takes some getting used to, and you may find yourself constantly adjusting it at first. If you play Expert on the console Guitar Hero's (like me) do yourself a favor and play the game on Medium or Hard first so you can get used to it. Once you do get used to it, it feels great and exactly how a portable Guitar Hero should. I am dissapointed with Practice mode. You can only practice at full speed, which I think kind of defeats the point. Just try to master the solo in "I Don't Wanna Stop" on Expert without slowing it down.
Guitar Hero On Tour is a must-have for Guitar Hero fans, and it's definitly worth checking out for rythm game fans. I think the only way you could possibly hate this game is if you hate Guitar Hero altogether.