You know, it never ceases to amaze me the number of people who justifiably spend countless hours researching for the "best" DVD burner available, purchase it, and subsequently end up nulling that burner by purchasing substandard media. But what is more unjust, is that the burner of choice is then given a poor review/opinion because it fails to perform up to its expectations.
Moral of the story: If you are going to put forth the effort and money to purchase the "best" burner...don't go buying the crappiest/cheapest media for it. It is not the manufacturer of the burner or the burner's fault. Remember: "Crap in = Crap out"
Personally, I use Taiyo Yudens. Yes, alot more expensive than those $0.69 per disk specials, but a whole lot more reliable. I have yet to burn a coaster with any of my burners (Sony DRU-500A; Lite On 411s; NEC 2500A).
Just my two cents.