It's cool, but it's got some usability issues for "playing along" unless you already know the chords, etc. The 1/2 time was also pretty choppy for me.

Rocksmith [1], which can be described as Guitar Hero for real guitars and basses, does a pretty nice job with the UI, difficulty levels and such. It would be cool to see a more open version of Rocksmith where you could load up tabs/songs on demand.

For reference, I wouldn't pay for Soundslice, but I have already shelled out $100+ on Rocksmith (Game, Bass expansion, songs, cords, guitars, etc) and am willing to shell out more (Ex: A Rush Pack just came out I believe.)

[1] http://www.youtube.com/watch?feature=player_embedded&v=k...