Thanks for the advice fellas.
Your right about the primacy thing I reckon and like you say I can imagine there are alot of people who've done the FAA IR who might gripe about the differences.
Having done both the FAA CPL and JAA CPL I think I've got a good idea of what the different styles will be. Like you say JAA is much more procedural with FAA focusing more an actual flying skill than procedure.
They're different but about the same in difficulty.