I do not know about US1photo. But I used US1camera, its a quite decent dealer. They had problems with my credit cards (they all showed incorrect credit though all was fine). I ordered from them a Tokina 12-24 Pro zoom for my camera. Shipped promptly and in excellent condition. All original package and included USA warranty...
Caution: they sell also products labeled as "gray market" products.. that shows in a lower than normal prices though they are not officially advertised as such. Nothing has to be wrong with these products, however they do not bear a US warranty and they were not imported by the official manufacturer dealer. Also these products are not intended for the US market, but otherwise are of the same quality as the officially imported USA products.