I started with Arita disks (mediacode RITEK), the disks I burned in the beginning worked perfect (and still do), they're 8 months old now. But when I was running to the end of my spindle they all started failing me, my Hitachi v47DJ wouldn't even read them right after the burnprocess. So I decided to order new DVD's with an other mediacode, I saw some cheap MediaRange disks (~10,- per spindle of 10) with mediacode RICOH JPN, I remembered Ricoh being great quality at the DVD+R disks so I ordered some and they seem to be working fine, burned around 25 now and all running perfectly, not one failure, not one dirty/unplayable disk error and booting really quick. The oldest ones are 4 months old now. Do you maybe got some kind of explanation for this phenomenon? MediaRange is a German brand btw (or well, their site is MediaRange.de).
I'm burning with a NEC ND-3540, with the latest original firmware (1.04) btw.
Cheers,
Mithradates