I bought one of these TDKs..The add for them in Stereo Review said something like ......the tape you would use to record Gods voice..The tape was quite heavy. I recorded MFSLs on it. I also bought a large number of the Teac Reel to Reel cassettes. I took them apart, put Maxell MA 46 minute tape on them and recorded MFSl records. Side a to side a and side b to side b (one MFSL per tape) I put the Teac reels in a very nice Cassette book called "Library of sound"which was made for storing cassettes. I remember butchering up a couple of the Teac reels doing this because it was tricky getting the reel pins out of the reel when changing the tape. The book had 11 Teacs and the one TDK Max-G tape inside. It sure looked impressive. I made one other "Library of sound" collection which I still have. This book has 12 MFSL cassettes in it. The stuff from the late 70s and early 80s was the best!! I still have 4 original teac reel cassettes, which go for big money on ebay. I like to "watch" my music as it plays (probably because I have ADD).