I would save a bit more skipping the e-flex gear, what is the io expander?
I'm not sure what this 'random cough' with the PFC is, I haven't experienced it, although I have t got anything to compare it to either.
Is the Haltec PP is plug and play then I wonder what would have been done to my original wiring to fit the apexi? I would need to revert the wiring to standard to fit the Haltec?