KBACKUP has been reported to work with tape drives on a QIC-02 
controller, many different SCSI  streamers and DAT  drives
as well as with the ftape  driver version 2.03 (drives controlled
by the floppy controller). It has reported not to work with
zftape  yet. It has also been reported to work with the IOmega
ZIPdrive
, both the SCSI version as well as the
alpha driver for the parallel-port version.
I am using and testing KBACKUP with a (rather old) Tandberg drive on a no-name QIC-02 controller. The QIC-02 LINUX driver implements the ``/dev/tape-reset '' device, so KBACKUP can use it to reset the driver at your request. I have not heard of any other driver supplying this pseudo-device.
For more details on using floppy streamers (the ftape and zftape drivers), see the Ftape-HOWTO.