Battalions of Fear and Follow the Blind are definitely must-haves. They were the only two that were remixed in addition to the remastering. The rest of the catalogue sounds a bit cleaner and sharper, but not nearly as much as BoF and FtB. The bonus tracks on the CDs are pretty neat as well, since this is the first time a lot of them (like the Lucifer's Heritage demos) have been officially released.