Put the Allsop DVD and CD Drive cleaner into my Panasonic DMR ES15 DVD Recorder and when it finished working, my problems with discs not finalizing or error messages stopped.  I also found that Verbatim plus DVD blank discs worked better in this machine than the Verbatim minus blank Discs I had been using so I'll be using those in the future too.  I was able to finish using the rest of the minus discs I had with no problems.  Product does what it's supposed to do.