I thought I'd just mention I bought from Stacks Bowers in the US a couple of weeks ago. Paid by credit card for a 2.5% supplement.
Got an email on Thursday saying it was being shipped and would be delivered yesterday. Some hope I thought, but .. slight delay because I missed the request to pay the vat (correct amount and reasonable fee from FedEx of £4 - rather cheaper than Royal Mail!) but it arrived this morning.
So things can go right (I wasn't sure how it would go as you occasionally hear of problems with US posted items) and in this case I actually received the coin faster than from some UK auction houses!
found today.... worth a show...
1840, Christian VIII, 1 Species Daler, Denmark
1835, Ferdinand 1st, Austria (Rarity) Homage in Vienna
1800, Charles IV, 2 Reales Mexico