Dude, 75% of the reason I buy DVDs (and LaserDiscs before them) is for the commentary. Generally, I don't care much for the deleted scenes and whatnot, but commentaries rule (most of the time).

OTOH, extras on music CDs are generally a load of crap, IMO. I don't really understand why it couldn't have been included on the US release if it was in the Japansese release. OTOOH, the ones I've heard have mostly sounded like ``deleted scenes'', which were mostly deleted for a good reason.