What's the Fastest DVD-RAM in the States?

I have the GSA-4166B and am looking for the fastest DVD-RAM disks. I have found 3X Panasonic…any other???

Thanks

Bob

Panasonic 5x

http://www2.panasonic.com/webapp/wcs/stores/servlet/vModelList?storeId=15001&catalogId=13401&catGroupId=25168&orderBy=msrp&cacheProgram=11002&cachePartner=7000000000000005702

5x DVD-RAM media sometimes cost nearly the same as 3x DVD-RAM media. I’m not sure if there are Taiwan-branded 5x DVD-RAM media in the retail market already.