When Brits travel to the USA for treatment, it is almost always for one of two reasons.
1). It is a new treatment, developed in the USA, which has not yet crossed the pond, and therefor is only available (at great expense) in the US.
2.) It is a highly speculative procedure which British doctors do not recommend, but the patient (understandably) is inclined to clutch at straws where death is the alternative.
I don't think you will ever find a British citizen who believes that you system is half as good as ours overall.