I like to think I'm pretty good at expert guitar on Rock Band (I can five-star almost everything, RB1&2 exported + ~400 USD worth of DLC), and I would just like to say that Force Feedback is fucking impossible for me. I do pretty well up until all the hammer-ons, at which point everything just falls apart and I fail. I'll keep at it, and one day I may be able to play it. Perhaps it'll become one of those songs I avoid for half a year or so and when I come back to it I find it isn't as hard to play as I remember. (I did this with "Flirtin' with Disaster." There was a time when I would fail it; now I can gold it.)
As for Indiscriminate Murder and Rocket Dragon, I five-star those pretty consistently now that I've had some time to practice them a bit. I've still yet to gold either of them; I'm working on that.
Gibli, you have my undying respect. If these songs are this hard to play with buttons, I can't imagine how hard they'd be on actual strings.