In those days, DAT and Exabyte tapes were more portable until DEC spun the DLT group out to quantum. But for a very long time 4mm and 8mm were a lot cheaper/meg. I still have a couple of working 9-track, 8mm and 4mm drives, but nothing from DLT. I don't know why, but I'd really love a 9 track drive for one of my DEC boxes..