Well, Arthur certainly doesn't build them himself, though I don't know who does (they took nearly four months to re-spray and swap some braze-ons on my frame, and I did consider going to find the bloke myself and explaining exactly what needed to be done, since there seemed to have been a communication breakdown along the way).
Arthur's a lovely chap, though - if you find yourself in Richmond, do go to the shop and talk bikes. He's really enthusiastic, and will yap endlessly about any aspect of cycling, from hardcore TTs to gentle ambles around the tracks and trails.