With my GP it took two letters to the NPPL medical advisor and quite a bit of hassle to get him to sign the medical declaration. Plus, he said the visit was considered a private medical and charged me £40; not the best GP you could hope for, but still a lot cheaper than a Class 2 medical.
WRT NPPL in Ireland, I started a thread, a couple of months ago (
Any chance to fly in Ireland on a UK NPPL (A)?) and the answer appears to be 'no' for the moment.