I get my blank dvds from Shop4tech.com. They're leda 4x blanks and I haven't had one single problem yet with them and on the rare occasion I get a coaster it's from a software problem. They're great for any kind of back-up and they're decently proced as well.
here's the link:
http://www.shop4tech.com/user.htm?go...cata=1&s_cata=