Thanks, it makes an exact match. One gets 100% SHA-1 sums, which as far as I know, can't be faked. The delta stuff is very clever, and is spreading here on MDL. As you might have seen in the 7 forum, as little as 20MB can change a +2GB original MSDN ISO into a newer MSDN ISO. A lot of bandwidth saved. Microsoft should offer it to their Technet customers Guess I should have caught on to you doing it the file way when you wrote that UltraISO said it got read error on DEPLOY.CAB with the black one. If read in ISO mode, UltraISO wouldn't have a clue as to what it as reading. It would just complain it couldn't read a certain block.
I am still new with making copys these OP discs, never really had too. If this Imgburn turns out ok, thats the way I will do it from now on. It is easier. Close as I can get to exact the better, I don't want to spread trash around if I can help it.
ImgBurn is quite good, not much can go wrong with it. I have never been a big fan of all the ISO mastering programs.