@Brandon > The retailer you spoke with probably didn't speak with his Pioneer sales rep to get updated information. I just called the sales manager and he told me there was a slight delay on the Pioneer end, but they should be arriving at the end of May.
I assure you there is nothing shady going on and if your retailer required you to make a full payment in advance of them having stock to sell you, THAT is the only thing shady I can see. I would understand if they wanted a deposit of like $50, but a full payment is a bit odd.