Just use the U.S for your PPL+hourbuilding, come home do your ATPL exams then do a JAA CPL/ME/IR it will work out cheaper in the long run and should not take much longer. Alot of schools in the U.S do the cpl but it does not work out cheaper it just mite save a bit of time, as far as doing a FAA IR I dont think its worth the hassel doing the conversion.