Have I been misinformed then? I thought the restrictions of a PFA type were that one couldn't fly outside the UK or at night or in controlled airspace?
Good news - you have indeed been (mostly) misinformed.
The bit which is true is that you cannot use a Permit aircraft at night, or in IMC for that matter. Or over built-up areas.
You certainly can use them in controlled airspace in day VMC, even in Class A if you get a Special VFR clearance. I use just that to cut through Heathrow's airspace via Ascot and Burnham sometimes.
There is no blanket restriction on Permit (PFA, BMAA or CAA) aircraft flying outside the UK. Several such aircraft have circled the globe in fact.
The difference with Permit aircraft as opposed to C of A ones when it comes to foreign flying is that since their UK permits to fly are not part of the ICAO international agreements there is no
obligation on other countries to allow you to visit. The good news is that almost all European countries have chosen to allow such visits anyway.
Some, like France and now Germany, have a issued a blanket permission and you can just file a flight plan and go. Others require you to fax them copies of your aircraft documentation first and will then grant you specific permission. One or two charge money for this (€45 for The Netherlands, €75 for Belgium) but most do it for free.
Switzerland bans microlights altogether but that is a rare exception.
In short, cross-Channel trips in PFA machines and microlights are, in the great majority of cases, no more trouble than in anything else.
By the way, where did your original misinformation come from?