Confabulous,
Challenge: Could I build the a/c here (Ireland) and put it on the N-reg? It's not PFA approved and I doubt it would be since the performance is so good.
No, I don't think you can. IIRC Aircraft registered in the FAA Experimental category can only operate outside the USA for limited periods of time (one month?), and then only with the permission of the regulatory authority of the country they are operating in. I've a feeling it was discussed either here or on the Flyer forums not that long ago - try a search on 'experimental' and FAA
I'm afraid if you want to build your own plane, then the route of least grief is a 'PFA approved' model, with as few modifications as possible,
Vans aircraft
seem to have a strong following and there's an
active e-mail group in the UK
Brooklands