I also wanted to ask about the picture quality that Disclord mentioned:

My partner saw T2 in CDS and says the Blu-ray finally gets the colors right, unlike the earlier discs. Of course, only the first DVD of T2 from Artisan used the 5.1 channel CDS mix - all other releases use the massively changed 6.1 mixes. So I have to sync the original DVD with the theatrical cut on the Blu-ray to get the CDS 70mm experience.

Which BD is he referencing that got the color timing correct - the first theatrical release from 2006? If that is the case then I am all for trying to sync the '98 Live 5.1 mix to the '06 BD picture but I have read that it is a nightmare to sync. I have not tried to verify if the same mix is used for the '06 theatrical BD but that would be interesting if it was because it would be at a much higher bitrate than what is on the Live DVD.

Also since the 5.1 Live mix allocates the surround mono channel from the original mix to both left and right you could simply join them back to 1 mono channel to recreate the original 4.1 mix. Am I wrong in thinking that?