I can't comment on the KW750 but, following the lead from Toyboy, I contacted the guy (John Sampson) who mods MF equipment and sent my KW500 PSU to him. Turns out I knew him as he worked for MF for over 20 years, and he was the source for any technical questions or issues. He was always straight and brutally honest (like working with Danny Ritchie/Dan Wright/Jim Salk etc), and he's also a big music lover. Bottom line is that he knows the strength and weakness of the MF range from their first amp, knows which amp/cd player is the sweet spot in the range and knows how to improve the models that are worth improving.
I should get my PSU back next week, when I do I'll add to this thread and keep my MF buddy (2bigears) in the loop.
At the same time MF is more 'main stream' than most of the boutique brands that are normally discussed on AC, so understand that the audience will be limited.