I go with Apple, faired well in the test & offer a decent compromise of quality & price (supported in report conclusions). They have never given me one coaster.
Same with the Sony brand -- never a coaster in about 30 DVDs made. Trying TDK and so far so good. Just don't buy Memorex (the ones sold at all the Best Buys). They are not approved by Pioneer and I wasted a lot of disks with them before I realized they didn't cut it). P.S. Sony's not on the approved list either but they should be.
Ha! Wish I read your Memorex post yesterday. :-) I just gave one to a client, and guess what. It skips like a schoolgirl in their player. Hopefully these Apples that arrived today will do the trick.