I think there is some confusion over permits to fly. Many warbirds and jets operate on them. These are issued and controlled by the CAA. The CAA have delegated authority for permits to fly on small aircraft, homebuilts etc to the PFA. a PFA permit aircraft is the one that many recreational pilots use in the UK.
I suggest that you look at the PFA website which has some excellent articles explaining what you can and cannot do on a PFA permit.
The main thing is that the routine maintenance can be done by the owner as long as it is signed off by a PFA inspector. This significantly reduces costs.
The downside is that there is no IFR, there are very few 4 seaters as these have only been allowed in the last year or so. There is no overflying built up areas. I have been told this means anywhere with a 30 mph speed limit.
You can go abroad, Ireland and France have given a blanket approval for PFA permit aircraft so no individual permission is needed. Other countries readly give permission.
As I mentioned the PFA website is a good starting point
www.pfa.org.uk or the engineering section
www.pfa.org.uk/engineering.asp