rudestuff,
You'll tend to find any regulator frowns upon converting a license or rating that was itself converted. In your example you could convert to the Canadian ME rating but it is likely that the FAA would not let you "re-convert" it back.
Case in point, I had a Canadian PPL, went to New Zealand to convert it to an NZ PPL. I did my NZ CPL, Instructor Rating and ME-IFR ticket plus a couple hundred hours of flying for a scenic operator. When I came home to Canada, Transport Canada made me re-do the examinations and flight tests for the CPL and ME-IFR (I never re-did my instructor rating). Their rationale was the
original NZ license was based on a conversion and even though I held a Canadian PPL, I was trying to convert a foreign CPL based on a foreign PPL that had been obtained via a conversion. Same with the Instructor Rating and ME-IFR - although my Instructor Rating had lapsed in NZ, so Transport Canada was going to make me do every hour all over again. Phew, that is complicated (and expensive) now that I think of it!
Along the same theme, had I gone over to Australia I would not have been qualified for the NZ-AUS open agreement on my PPL because it was a converted license. However, because I obtained a CPL in NZ, my CPL was valid for the conversion - go figure.
License conversions tend to be murky waters with a couple loopholes that are very quickly filled in once discovered. As others have pointed out, countries differ on their application of PIC, Dual, Co-Pilot, Night - you name it. Other times they have the same definition but different requirements - for example NZ needed 5 hours night for the CPL, Canada needed 10 hours - so even though I had an NZ CPL, I had some extra night time building to do.
Where ever possible, I now suggest to anyone that they just do it all with their local regulator. Otherwise, they end up spending more money one way or the other for what will amount to a couple of hours that no one looking at the logbook will really care about.
Good luck!
