I too would be curious whether anyone is working on it.  In fact I was
just perusing my tech manual wondering whether I should give it a try.

I've no idea about the performance compared with the conventional KA630.
I am fairly sure the I/O will be slower as the KA410 uses a 16Kb static
memory buffer between the HD9224 RD/RX controller, the NCR5380 TK
controller and the KA410 memory.  I'd love to see us make use of that
SCSI controller to talk with faster/cheaper/bigger new drives and misc
devices.  The LANCE EtherNet controller does use DMA.  I wonder how memory
performance compares with the Q-bus boxes (given a PMI with the KA6xx)?

Most folks may think of the video approach but I prefer the simplier serial
port console approach to start with.  Getting a serial console is as simple
as on a Sun 3 box (well, almost, you need to short pins 8-9 I believe)...

I guess what makes it harder is the lack of any partial port (ala 4.4lite)
to the KA410.  I think Ultrix is all I saw on the VS2000 system (too bad
DEC didn't release (that I know of) the driver stuff as it did other stuff
to BSD).