I'm not sure what the quality is like, but Microcenter has 10 packs of Windata 8x DL DVD+R's for $9.99. I picked up some yesterday just because they were cheap, but I haven't tried them yet.
I purchased 3 packs of these back when they had them on sale for $7.50. I have to say....I have made completed copies of dvd's with NO problems yet. Watched them all and they are just as good as the original...and the media is JUST FINE.