Technically all you need to know about the Quest Mode in Guitar Hero: Warriors of Rock is that Gene Simmons from Kiss is in it, but some additional information on the Warriors and their powers doesn't hurt.
I'm getting a little tired of music games at this point, but if I had to choose between Rock Band 3's more realistic approach to playing and Guitar Hero: Warriors of Rock's Quest Mode, I'd probably go with the latter. The past couple of generations have produced games with no real goals other than to play through all the songs and get high scores. I wouldn't mind having an actual game to play.
Besides, if I wanted to play a real guitar, I'd find the one I have stuffed in the back of my closet somewhere.