FAA PPL
Chewy,
If you train in the US, it doesn't matter whether you obtain a JAA PPL or an FAA PPL. Either way, you will have to do more hours dual on your return to the UK. This is for three reasons.
Firstly, UK airspace in general tends to be more conjested than much US airspace, so you have to be on you toes, and ready to use British radio technique.
Secondly, our weather is VERY MUCH less predictable than theirs.
Thirdly, British clubs seem to be of the opinion that there is more variability in training standards among those returning from American establishments, so they feel they have to vet carefully anybody coming back from there.
However, once you have done your dual on returning from the USA, you should have no further difficulty in establishing your familiarity with UK conditions as your UK dual will be recorded in your log book.
One thing to bear in mind is that if you do a JAA PPL, you will then be compelled to have a life long relationship with our unbelievably rapacious CAA, who will charge you royally for every single thing.
For example, if your ambition is to fly in instrument conditions, then if you have a JAA PPL you will either be limited to obtaining an IMC rating, which has limited privileges.
Or, you may obtain an FAA Instrument Rating and use it with your JAA PPL, in which case you will still have to pay £70 every year just for the CAA to put a rubber stamp on it!
If you have an FAA PPL and IR, I don't know what the figures are for renewal, but I am certain they will be a fraction of what you'd pay the CAA.
Either way, I still think it is better to train overseas (e.g. USA) as you can go somewhere where the weather is dependable and get the licence over and done with all in one go.
Confabulous' advice regarding choice of the best month to go over is correct. Check through the search function on this site or with your school of choice to find the best time to go.
Best regards,
Broomstick