They are made in Taiwan. I have already used about 50 of them to back up some important data. (Cannot afford a Tape Drive right now).
Do you think I should make another copy on something more reliable like Verbatim or Kodak just in case?
No, the newer Ritek CDRs like thoose of the IBM are proberly the best CDRs out of Taiwan right now and are similar to the Maxwell also made by Ritek. The use of phtalcyonine dye is a good sign that the data will now deteriorate within 50 years, so if they are on special go get some more them !