I don't understand the strategy of various companies right now to provide pre-orders for products deliverable in 4 months at huge discounts when compared to CURRENT difficulty. Why don't they just wait until they have a product to sell and sell it at premium prices?

The uncertainty the miners have to go through when placing such an order is mind staggering. I cannot escape the conclusion that either these offers are of the same kind as from butterfly labs (dishonest, offloading delay risk) or their pricing is such, that they expect more return on their product when asking for the money now (dishonest, charging too high).

Of course there is also the slight chance that they haven't figured out proper pricing yet. Buyer beware.