I agree, Quantegy 456 will be fine and I would prefer it to RMGI SM911. Tape does not age like bread or bologna. That is, there is no meaning to the term, "Fresh Tape" as some sales people use it. 20-year-old unused tape is no different than 2-week-old unused tape. They are both new. I have 40+ year-old tape that is as good as new.