I've always used Mitsui Gold if I wanted a back up to last, anything less you'll be re-burning on occasion. I have some that I backed up & in use since '97 that are still working like new. They do cost more, but it's worth it if you really want to have a solid archive of your discs that will last over time.
http://www.discmakers.com/shop/ItemDeta ... -030-00033