Congratulations! My worst offence was having my handbag spike the metal detector at the Embassy THREE times - one was the clip on my purse, then a teaspoon I carry for emergencies (doesn't everyone?!) and finally - when their gritted teeth and lack of British humour was at its worst - we found Son#2's metal pencil sharpener, forgotten at the bottom of my bag.

But yes, they were very helpful when I *was* finally let in, and I don't remember it taking too long for the tax number to come through.
^_^