I would take the Pax post if it's offered rather than wait 6 months. I don't know any more what the cost differential is, but the end qualification is equivalent and you work just as hard. Pax being American has more money and more toys but the basic academic and flying syllabus is the same.
Having said that, if you are a civilian (non-government) there may be other issues to do with acceptance for flying in the USA, as there are with anyone doing initial flying training (not recurrent) in the form of TSA requirements. I have no idea how that may affect you, if at all, but it caused us a lot of grief for S92 training.