When I first elected to change from PPL to NPPL I passed all the relevant papers concerning the issue to my GP. I have recently had my fourth renewal with him and he still can't come to terms with the fact that all he is doing is countersigning my declaration as to fitness to fly. He therefore carries out s short examination - blood pressure, eyesight etc - before signing. For this he charges me £26.00. Still cheaper than using an AME.
The NPPL of course restricts me as to aircraft I can fly (The Piper Arrow is now out) but I can still visit all of the UK including the IOM, Northern Ireland and, more recently, the Channel Isles. I do miss France however.