well from my experience of opening that set, 3 btw, i only got 1 uxie per box. now they might have been bad boxes, but there are still possibilities that it might happen. so if you think about it, you spent $60 in hopes of getting that one card, but if you spent that same amount of money now, you would have between 3-4 uxies.
Well, when we opened our two boxes of IFDS we got at least 4 of each non holo rare, and 9 Rapidash. But it all depends on how much Uxie goes up in price over the next couple months.