As an American, I also prefer the British border security folks. They're polite and they have a sense of humor, but are still thorough.

Last time I went to London for work I explained that I was coming over to set up a network. What followed was an extended comedic interaction about how I was pulling the cable, the size of the spool needed, and whether I had flushed one end down the airplane toilet to let it unspool as we went.