best thing to do in my opinion is look at mega cheap brands and buy a single disc maybe a couple or a small spindle (bought a 10 disc spindle for $5 australian the other day). then you burn those and test them on any dvd device you have in your house and see how well they work. it also depends on whether it is for dvd-video or data. not to mention there are dvd+r, dvd-r, dvd-rw, dvd+rw, dvd-DL, dvd+dl and dvd-ram discs so it depends on a lot. anyway once you find out how well mega cheap discs work you might be able to find a brand that is actually pretty reliable like i did and you can just buy a big spindle. finally i would like to point out that a dual layer disc is not equal to 2 single layer discs. 2x4.7gb=9.4gb. dual layer disc=8.5gb.