This is a copy of a post from CBM-hackers mailing list, from Steve Gray. I am going to give it a try.
"..I've had good success transfering 8x50 disks using a B128, serial cable, cbmlink, and my own CBMXfer (not really required if you can use the cbmlink commandline interface). The nice thing about the B128/600 is its built-in RS-232 port, so there are no specialized cabling or adapters to build. .."