I am sorry to admit that I had this on preorder at buy.com since the announcement
Only got to half way through Empire so far.
Overall the quality of the image and sound is really good.
As for the mods specifically, most of them have a much more 'connected' feel to them. Especially compared to the original re-release if you can call it that.
But even now, some of the added beasts etc still look fake. I suppose the better quality of the DVD allows you to see some of the things that the VCR would hide.
Having seen these movies so many times you can see so much more in every scene, even for the untouched ones.
I will get to Jedi this weekend.