Talked to tech support today. New PX-716A replacement (TLA 0308) is good to go. 16X burns on Taiyo Yuden…and some Verbatim. Out of the same cake pak…I will get a 16X burn at 5:45 and a 12X burn, 8X burn and more. Having problems with the DL +R at 8X on my PX-740A. Will burn the first layer at 8X and second layer at 4X…Verbatim quality all over the road. Plextor says that Verbatim is using a different manufacturing plant and things have gone from good to bad to worse. If you want to keep burning Verbatim at 16X (or at least ones that will), don’t update to the new PX-716A firmware 1.09, due in the next few weeks. It will remove Verbatim from the high speed list.