Media = disks in this case.
If you have to use RW disks, I'd stick with Verbatim brand. Burning at very slow speeds is not recommended with modern burners and modern media. I don't know the capabilities of your burner however.
Verbatim, Taiyo Yuden and sometimes Sony are reasonably good choices for media if using ordinary recordable disks, not the re-recordable rw disks.