Finally assembled my Heavy-9 with the new mill-maxed PCB – it’s a dream. I initially thought the north-south orientation of the ‘+’ and ‘Enter’ switches on the numpad may have caused issues in stability since there is no plate between the stabilizers for the switches latch onto, but the combination of mill-max sockets and the stabilizers took care of things. Just something to note for those who plan to keep the stock fc980m plate.