I put in an order there but canceled soon after. Not only do they not ship until June 4th (and couldn't confirm that would be definite), they said they can only do the pre-approval and credit check for Sprint (for a transferring customer like me) until that very day, which was a bit of a bummer. In the end the pre-order at Radio Shack or Best Buy seemed better if you wanted the phone immediately because they've set up everything with Sprint already.
However, I've used them before for phones already in stock, and they've been quick and efficient, so in a few weeks it might be a good bet.