I did my PPL with them. I asked them about the JAR Complaint PPL. They did inform me that it was a FAA PPL with UK RT, Aviation Law and ground school to prepare you to fly here.
I did not bother with the JAA PPL as I did not see any advantage of getting it. I checked with the CAA and they informed me that I can fly G reg aircraft in the UK and overseas. I can also fly at night if my foreign licence allows me to do so.
CAA website:
http://www.caa.co.uk/srg/licensing/faq.asp?faqid=208
A licence issued by any other ICAO Contracting State (including a JAA State that has not yet been recommended for mutual recognition) is also deemed to be valid under the ANO for the purposes of flying a UK registered aircraft, providing that the licence and medical are valid in accordance with the rules/laws of the issuing State, and the CAA does not in the particular case give direction to the contrary. However, Article 21 (4) (a) states that the holder of such a licence cannot:
1) Act as a member of the flight crew of any aircraft flying for the purpose of public transport or aerial work or on any flight in respect of which he receives remuneration for his services as a member of the flight crew; or
2) In the case of a pilot’s licence, act as a pilot of any aircraft flying in controlled airspace in circumstances requiring compliance with the Instrument Flight Rules or to give any instruction in flying.
This one is from Bristol Ground School where I plan to take ATPL writtens:
http://www.bristol.gs/abinitio.htm
"Whether you decide to organise your own modular training or work through one of the structured modular course providers your first step is to get a Private Pilot’s Licence (PPL) issued to ICAO standards. Nearly all PPL's meet these standards, it doesn't matter whether you hold an FAA licence, an Indian PPL or a JAA PPL. One of the very few licenses that does not meet ICAO standards is the new British National PPL (NPPL)."