Gareth,
Without having looked at their website, or having any knowledge of PEA, the FAA license that they will get you is (as GT said) an ICAO license.
If you want a JAA license, you will have to convert it. There are lots of threads around on converting ICAO licenses to JAR, and full details are in LASORS. I don't have any experience of this, but from reading about other peoples' experiences it seems that it's generally quite difficult for low-hours pilots. If you want an FAA and a JAA license, it seems to be easier to get the JAA license first then convert it to FAA.
FFF
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