Pj do a modular board for their 15000W, ie they have sub boards for the 4 x 6off FET,s.
The 8000W PJ board, only 4 caps, was originally there early 15000W board, and is what I designed our New Power board around. But this early PJ board needed careful assembly and good soldering, something sometimes that PJ was lacking with QC.
I have a couple of 15000 PJ's with the FET sub boards. These seem to work well if the PCB's are conformal coated. PJ boards seem to come covered in solder splatter and flux remains. So all need washing and coating properly.
We discussed on here, somewhere, that the PJ resistor ladders with humidity, etc, tended to wander a bit.
One of my 15000W PJ boards OzInverter sits outside in a cupboard attached to a shed, so it gets everything.
However, that particular OzInverter never gets switched off.
If I recall, 'Oztules' got good results when he did a swap out on a PJ board, and replaced the PJ control board with a OzControl board with the 8010 chip, and modified a PJ Power board.