I had a problem with Ks arcade in the past (3+ years ago). I was having
a problem with a Williams System 3 machine that would start a game but
would reset when particular targets were hit. I removed the playfield
connectors and verified it was somewhere in one of the two main boards.
Sent in two boards .. one was an MPU board that K's arcade rebuilt
sometime in the past and the other was the driver board.

He convinced me the MPU was fine and the Driver board was bad (so bad
that I needed a new one!). I got them back and the problem was still
there! After a lot of learning and research I figured out that the roms
in the MPU board were for a different machine (although marked for my
machine). I sent for new roms (from someone else!) and then everything
worked fine. So postage to and from K's ($30+). New Driver board which
I didn't need ($175 - $15 trade value for my perfectly good one!). So
that was $190 when all I needed was the correct roms.

This experience has been the worst I had in my pinball hobby. I hope
others are better than mine.

Mike V.