I once worked for a Global Logistics Company based in London - none of the Senior Execs used the British System. Most had Doctors at UPenn and would bring their families here for medical care.
Circa 1978 while living in the UK the health care system was good but not perfect. My son was born there, and the care was excellent. Acute medical as in birth or injury was excellent. Normal care for chronic conditions were not. You just stood in line. For such I just paid for out of NIH health services as I could do such. Most could not.