They were used
on some MSX home computers, although I have only ever read
about them (and seen pictures). I don't think they were commonplace
outside of Japan and Korea. They were sort of a cross between tape and
disk media; data was written sequentially in a spiral pattern on the disk.
MSX with 3.25 disks? Is that the QD drive?
No. QD disks are 2.8". Several drives are mentioned here:
<http://www.faq.msxnet.org/hardware.html>
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