Almost two decades ago I had many hours of delay to get through US immigration twice on successive trips. I have not returned since. If a country thinks so little of my wellbeing and time then they don't deserve my tourist dollars. I have happily visited many many other corners of the world since with no memorable problems until an unacceptable delay travelling through Heathrow last year. Sadly I can't avoid UK immigration, but I'm sure there are many in the world who can and will.