I'd like to know their video and sound quality.
and also how interesting their "making of" featurettes are.

You know what the answer is... Standard answer #1:

For the age of these two movies, they are the best in terms of video and audio than ever before seen/remembered. It's so hard to describe this quality as there is so much room for subjectivity. I'll qualify. I really, really liked the video and audio of Deliverance, I was very much surprised at how good it was. I was less surprised with The Shining, but just the same I feel it was really good in terms of video and audio. Deliverance was remixed into 5.1 and it sounded really, really good. It was anamorphically enhanced and was mostly really, really clean and devoid of showing it's age in terms of wear. It was bright for the most part and had great color. The Shining was mono, not that great, but better than at a drive-in theater. The video was full frame as Kubrick shot it that way and it was dark and grainy and it showed it's age more.

The featurettes were longer and more in depth on Deliverance, but it was great to see Stanley and hear the scoop on Shelly Duvall on The Shining.

If this doesn't help, just buy them and develop your own conclusions. You'll be buying the best as is currently offered and I whole-heartedly recommend both of them. They're GGGGGRRRRRREAT!!!!

RVN

Deliverance is a really good transfer for a film from 1972 IMO. It also has a trailer and a pretty neat 10-minute documentary on it. For the price it's excellent. If you like this John Boorman movie you should try Hell in the Pacific, The General, and Excalibur, sadly the only four of his films to hit DVD yet. Really underrated director though.

just rent them and decide for yourself!