re can't f;y in france
Sorry my earlier post was not clear. The point is that you cannot fly a G reg abroad on an FAA licence. With the FAA ticket within JAA land you can fly an aircraft within the borders of the country in which the aircraft is registered. However you cannot cross borders with an aircraft.
You are quite right re Biannual flight review. I did mine whilst on hols in South Africa - just need and FAA instructor to check you out - location not important.
I suppose though that this all theoretical until somthing goes wrong or until I send my logbook off to Gatwick to get my JAA CPL and they tell me all my P1 time is invalid as I don't have any type ratings and therefore couldn't possibly have flown anything without supervision, an issue that I understand some folk have had following doing the LA traffic watch thing. We will see shortly!
Insurance wise as I fly my own machine, pilots are 'as approved by the insured'. Despite occasional reservations I approved myself and that was that.