If what you're really after is a "read anything" system for archival
purposes, why bother with someone's FDC? There was a time when processor
horsepower was limited and LSI didn't mean what it does now and an LSI FDC
seemed like a good idea.
That was then and this is now. If you can find a 64KB FIFO (salvaged from
an old video card maybe) or a bunch of 8 bit counters and some SRAM, you
can build your own version of a Catweasel and read just about
anything--including those Victor 9000 or Motorola VersaDOS diskette or any
number of bizarre copy-protection schemes. You can use an 8255 for drive
control and the rest is mostly LSTTL glue. Writing is a little more
complicated, but reading is simple.
When talking about multiple controllers on a card, it seems that a simpler
approach might be a bit more flexible.
Cheers,
Chuck