Actually, those discs don't sound terribly appealing.
Disk 1 carries both the theatrical and extended versions via seamless branching. Given that the current extended editions are split across two discs, doesn't this mean they'll have had to use much higher compression rates, which result in lower picture and sound quality? I would also be doubtful whether the DTS and commentary tracks exist on these discs.
The second disc has this new documentary listed, but there's no indication of any other extras.
All of which makes these sets sound less appealing than the existing "Extended Edition" discs.
I guess they're worthwhile if you don't own these films on DVD yet. Otherwise, they sound like something to pass on.
Besides, isn't it almost time to abandon DVD for HD equivalents?