I have well over 1000 cassettes and still bring them out to archive/back-up. Many of these are live performaces and I used TDK SA and TDK SAX in the 70's and shifted to TDK MAR with the cast aluminum shell. I probably have 300 MAR tapes. I also used Maxell UDXLII when the TDK was out of stock. For many of the tapes, I archive to VHS HI FI. These days is it more economical to transfer them to CD. The VHS HI FI does a great job and is very reliable. In 1984, I purchased a Mitsubishi VHS HI FI and I have 20 year old tapes that still work fine. I got away from the reel to reel 1/4" machines though.