As a side issue aimed at people with medical problems....consider doing an FAA PPL. This gives you full privileges on a G reg aircraft [as well as N reg obviously], the medical is far less stringent, and lasts longer....[and you bypass the "wonderful world of JAR"....
]...oh and it is an ICAO recognised licence, which the NPPL is not.
Not knocking the NPPL, just my view....
Cheers
EA