>> I have been careful not to buy SMR drives, but AIUI they are cost >> effective for large sequential write workloads -- e.g. music/ photo/ >> video/ ISO files, backup/ archive tarballs, images/ clones, etc..
AFAIK SMR drives are just as good as PMR drives when it comes to reading, so it should work fine for a read-only OS partition. I wouldn't recommend it for a swap partition, OTOH :-) Stefan