Seriously, how awesome would some ELP be? I haven't seen it mentioned and I'm listening to a greatest hits CD at the moment which prompted me to post a thread =p
I'd probably take The Barbarian, Tarkus, and Karn Evil 9 and I'd be totally super happy. Although I don't know how well 20+ minute songs would work in RB.
Vocalists wouldn't be too happy, but make it DLC and **** the vocalist =p
Or just release Queen and Boston the next week to make vocalists happy XD