A few years back AJ Palmgren helped me recover data from a S8000 tape using his hacked QIC drive. He fed the data coming off the drive into a Saleae logic analyzer. I took the gigantic dumps and wrote a software decoder. The data on the tape are MFM encoded. It went pretty well and I could recover the entire tape.
http://www.datormuseum.se/computers/others/zilog-s8000/extract-s8000-tapes So you can read these tapes by other means than the original drive. It just requires some tinkering with the drive to get the correct tracks and some software.