IIRC the reason why the guy who did the anamorphic version said that using the 2.0 option was a lot smaller than the PCM, and that with the chapter stops & commentaries he didn't want to lose too much of the video qualtiy?
I suppose everyone is waiting for a good dual-layered dvd set - I know there's been a couple of dual-layered sets - but they havn't gone down to well in comparison to the single layered versions - one of the d-l sets apparently only used half the 2nd side and some mentioned the pic quality was WORSE!
Hopefully when the combatibilty issues of dual-layered dvd are more known (and the d-l dvds themselves become cheaper) then someone will do a fully utilised dual-layered anamorphic 4 disc set with PCM sound - in the style of the Deinitve Collection laserdiscs (now that's a mouthful
)