PPL in USA
I have both UK CPL and FAA ME/I and I would suggest the following:
By all means do your PPL abroad - you will save money - however it will cost a LOT more than you think it will - its likely you will need more time and there are a lot of hidden extras that they don't advertise suck as tax and fuel surcharge - but it will still be cheaper in the USA.
Do not do an FAA PPL - it is much harder that the CAA PPL: you only have one written exam, fair enough, and they do publish all the answers, but not only will you have to learn a lot of regulations and stuff that you don't need, much of it will be of no use to you outside America. The hardest part of the FAA PPL is the oral exam - you have an unlimited 'test' with an examiner who can ask you whatever they like - and they can fail you without even seeing you fly. My oral exam was nearly an hour long - and most of it about USA regulations which are useless for you flying in the UK - and there are a lot of them, buy a copy of FAR/AIM and find out, you m,ight as well as you have to learn it.
True, there are more CAA exams - however these are relevant to flying in the UK - the oral will be almost non-existant and the flying test will also be much easier than the FAA test - various exercises such as turns around a point and S Turns aren't required by the CAA.
Whetever you chose. budget for more time than they say you'll need and expect to spend some time with an examiner here when you come back - schools will not hire a plane to you unless they've checked me out, and believe me eyou will need a couple of hours with an instructor here even if you do a CAA PPL - much more time will be required if you do an FAA PPL.
If you do the CAA PPL take all your exams here before you go: that's one of the most time consuming elements.