i think dave flood's header would be the go if you were planning to do other mods to the car. the fact he can take into account things like changed redlines, cams, compression and all the other little things involved in doing a serious build up means that he could make something specific for your machine. think of it as comparing a pre-programmed chip to a programmable ecu.
back when i was shopping around for a header, the jdm 4-1 version was extremely hard to find and over 1k.
who actually makes the mugen replica?