Taiyo Yuden 8x DVD-R

A South Korean retailer has TY 8x DVD-R now. The price is 10,000 Korean Won for five jewel case pack, 2,000 Won each. Since Taiyo Yuden 8x DVD+R can be burned at 12x speed with LG GSA-4120B and Plextor PX-712A, will there ever be 12x DVD-R speed for TY 8x DVD-R as well? If not, for what should one buy 8x DVD-R paying more than for 8x DVD+R?

Do you know where I can buy this media on the internet? Or any other 12x compatible (listed below?)
Plextor 12X (4X ~ 12X) PX-DVD+R8JC1
Maxell 12X (4X ~ 12X) D+R47C.1P, D+R47C.1P5S
Ricoh 12X (4X ~ 12X) DRD-8XCW5, DRD-8XCW10, DRV-8XCW5
Taiyo Yuden 12X (4X ~ 12X) DVD+R47TYA, DVD+R47TY5PA


Well, i know you can buy the 12x/8x +r discs from the source direct, plextor.com