Well there is nothing to say you have to jump in head first and get a fATPL straight away ! You can do it in a modular fashion, which is what I am doing / have done.
I work for a living, got my PPL back in 2K, went to the US, got my IR in 2001, flew for fun since then. Then I went back in 2003 and got my FAA Commercial MEIR. This has put me in a very good position to convert to JAA, as the average conversion course to JAA fATPL is around £5000-£7000.
My Class 2 medical is up for renewal again this March, and I'm thinking of getting the Class 1 instead, and if I get this, doing the ATPL ground exams. Once all this is out of the way, I may convert to JAR.
So far I reckon I've spent $30,000 on flying, add another £10,000 to that for the JAA conversion and I could end up with an FAA CPL ME IR and a JAA fATPL with in excess of 350 hrs.
Why pay through the nose when you don't need to? There are now companies in the US which will take an ICAO (JAA/CAA) PPL holder with around 150 hrs, and take them all the way to JAA fATPL (including FAA CPL/IR) for less than £14,000 including all conversion costs.
Cheers
EA