Oddly enough, I have . . . between three "different" users, actually. One from Arizona, one from Mississippi and I cannot recall the last's location (somewhere in the South, perhaps Alabama).
I did not partake in their Buy It Now auctions, as their low feedback had me wary at first. However, after winning a 9764 Republic Frigate and receiving it within two days at an incredible price, all of my inquiries of suspicions disappeared (greed overtook me).
Between the three, I purchased seven 9764 Republic Frigates, four 4195 Queen Anne's Revenge, three 7946 King's Castle, and two 8129 AT-AT Walker, winning each set well under $90.00, also with free shipping. I managed several 10210 Imperial Flagship (!!!) purchases and some UCS Star Wars buys at insane prices, too (not under $100.00, but still quite discounted). Each shipment arrived in record time and while each package did come straight from shop.lego.com, my name and address were never on the slips. It was always a different name, and no two slips were the same.
I found that strange, and I also found each of their stock strange. I mean, I was essentially eBay stalking these sellers. I may have won about twenty sets, but I had probably bid on twice that amount, all at one time. And, even then that was only a tenth of their items as these sellers had hundreds of listings, all for these relatively newer sets . . . but, all ending within 48-72 hours at the most.
They were active for, maybe, two to three weeks and then that was it. I'd notice the same items being sold by "new" users, but my spree had been sated.
It is totally suspicious; I would not dare deny that. But, what do I have to complain about? I got a legit item and paid for it. I don't know, though. If I had to guess, I'd say that it was an internal job.
'Grats on your 4184 Black Pearl, though.

I only managed one, around $85.00. All the others I saw were actually jumping above retail price.