Yeah dude, if you really enjoy music type of games like GuitarHero or Rock Band etc. you should really find an opportunity to try out the originals designed by Konami.
If you want a challenge and eye opener, you gotta try BeatMania, GuitarFreaks, DrumMania. The musics on those are just fking amazing, of course they're not songs that you're familiar with like Rage Agast or Metallica but it's a whole other ball park.
Let me show you just a few videos of what I'm talking about:
http://www.youtube.com/watch?v=-e7cpUIxq3Y
In this video, the song I was referring to "V" starts from 2:29. Also "Aurora" is not bad as well.
http://www.youtube.com/watch?v=KNvzECgJBxU&feature=related
In this video, somebody is going Superman on "HappySky". He/she isn't hitting enough combos but then again who's got true Superman fingers? At 7:25 "One More Lovely" is also pretty extreme.
http://www.youtube.com/watch?v=k6-pAjzeG7U
All right, now this is my all time favorite song "Star Field". It's not as hard as the others above, but it's just so fking bomb to play and listen to.
Anyway, I hope you check out all 3 of these vids and try the game itself if it is available in your area :)
Oh lol btw, this is why some people who had previously played Konami's music games then tried Rock Band, GuitarHero finds them silly in terms of difficulty comparison..