Not going to start another debate about how good/bad F-CONs are but consider why most high HP cars from Japan use it over the PFC... also consider why a seemingly "piggyback" system would be preferred over a "standalone" ECU.
I was sceptical to start off with too... but after talking to Tom, seeing it done, and driving my car - I'm converted. Talk to silver r32gtst from here, he's running one too.