I recently bought a pack of Matrix brand dvd-r media from shop4tech and I am having a lot of trouble with it. I used Nero Express to try and burn data onto the dvds, but for some reason, more than half of them would not work. I tried using verbatim dvd-rs and they worked 100%. The Matrix ones would not close properly, I think. The last few hundred mbs would have a cycle redunacy error when I try to copy them. I wasted almost ten of them already trying to make them work.