Cheap, unreliable.
Radius Technology DVDs ID as "OPTODISC" brand media. (That is, OPTODISC makes the discs for Radius). OPTODISC media are generally found to be lousy: poor compatibility with many burners and many "coaster" (unreadable) burns. Amazon has high quality RIDATA blanks for a little more money. I highly recommend you buy them instead. Save yourself a lot of headaches and (if you store anything of importance) heartbreak. There really *IS* a significant difference between very cheap DVD media (like these) and better DVD media (like the Ridata).