I would grant them a negative number if I could. I paid them $1600 to repair a board and it returned to me not working. They test in a simulator which in this case proved to be unreliable - the Mitsubishi board DID NOT WORK after I got it back! My production machine was down and I could not send it back to them since they were not capable of repairing it the first time. A $1600 MISTAKE I hope the rest of you will not make. I had to send the board to Mitsubishi to get it repaired - ADVICE - stick with the original manufacture for repair - you will be much more satisfied. They only offered their repair warranty as an excuse and offered no compensation for their unreliable repair process. I shared the repair report with them, but they made no effort to correct this situation. DO NOT HIRE them if it is a critical repair!