In reply to Guy Hurst:
> Some US sites will ship to the UK, others won't. There doesn't seem any logic to which ones do what.
Yes there is a logic and reason. Recently bought a Vitamix as a wedding present oddly even after UK taxes it's still 30% cheaper when bought by an American consumer in America. Take a look at the REI website and they're a bit more honest in admitting that companies impose a ban on selling abroad. It's why the U.K. is known as 'treasure island' lots of companies make most of there profits here.
Also worth bearing in mind.... what happens if the item sent is the wrong size, color, missing bits, damaged, lost or needs warranty work. If you're a regular traveler to the US then it might be worth it but not worth it otherwise in my view.