70 mustang
You forget that the brits invented flying, won two world wars single handed and abolished slavery; I won't mention their trade in the poppy.
I have been fortunate to have flown with instructors from four continents and at least a dozen nationalities; there are good, bad and a absolutely terrible ones amongst all of them. My first lot had no experience and were hour builders..one making an airline career and the second in the regulator as he wasn't even good enough for the former and continued to instruct.
There are many ways to skin a cat, students take in knowledge in different ways and in my humble opinion a good instructor does not need to be an above average pilot but does need integrity, the ability to listen, observe, think, be self deprecating and honest.
I remember a conversation with a GSA (RAF gliding) instructor with 1000s of hours who told me that the British Gliding Association would not accept his experience because it wasn't up to their standards!
One of the many Johnnie Foreigners I learnt from was a 21 year old, pot smoking Frenchman when I had 10,000 hours.