If you've already got a UK JAA/CAA PPL(A), then helicopter training in the US might not be such a bad idea as you would only have one exam to sit in the UK (as you have the others) and you are already versed with UK airspace and radio.
The R22 won't allow much for "Christmas" weight gain but the Schweizer would have that lee-way plus it's a nice helicopter on which to train (ah, the sound of a can of worms being opened - music to my ears!!). However, it would be best to train on the type that's nearest to where you live if you want to self-fly hire later and do your annual checks.
Cheers
Whirls