Thanks guys.
young skywalker's point about ratings is my concern. I have 80 hours at present, and require 150 to start the FAA CPL training, and 250 for CPL issue. During that period, I'd hope to get an ME/IR (and obviously CPL), which given I'll ultimately need 250 hours with the right mix of flight time, will probably involve some hour building.
I can't see how I could get an FAA ME and IR in the states based on the certificate issued on the back of the CAA PPL. Is it possible to get the ratings based on the UK PPL, given I'll be going for an FAA CPL?
Thanks for the advice on getting FAA PPLs in the UK - I heard through the grapevine that there is an FAA examiner currently working part-time at Bonus (Cranfield). Will definitely see if he can help with the test for an FAA PPL.