I suffer from lupus and went on a message board where a lot of americans go and i was horrified hearing stories about how people cant afford the anti-malarials that i get on prescription, and how they have to travel all over the place to get a decent diagnosis, both of which make the illness much worse. Makes me very grateful that I have a GP who can refer me to an appropriate rheumatologist who can monitor me over 2 years to see how i change, and prescribe me medicines.
So based on that alone I think the NHS is superb. I know it has its flaws, but at the same time its treated many of my family and friends who have had serious illnesses, and they haven't had to have their situation worsened by money worries.