I will only buy Taiyo Yuden DVD -R 8X media after having been surprised to have about a 8-10% failure rate with Verbatum DVD +R 8X using my Memorex True Image 8x burner, unless I drop the burn speed to 4x. In contrast, I have burned about 1800 of these new Taiyo 8x DVD-R with only 1 failure (my fault running another program at the time).
I used to deal with Meritline, but have had serious problems with Ritek and other substandard media substituted in violation of advertised Taiyo (PioData) brands. More recently had a problem with CDDimensions.com adding a charge because they didn't calculate it correctly on checkout (which I am disputing).
After buying thousands of DVD media, I don't recommend Meritline or CDDimensions.com anymore. The best I have found so far is mediasupply.com (make sure you call them for the order).
This is the best price I have found on bulk DVD-R 8X Taiyo Yuden media 50/cake. For example, it was $298.50 for 200 today, including shipping (must call them).