I will believe the product when I see it. And if I am wrong and they do deliver, then they are retarded for selling their secret.
Legitimately, these would need to be "burned in" by mining. So they can do a little of both -- mine some for themselves (while difficulty is low).
Watch for shipments to be timed right at each difficulty adjustment. (e.g., mine before the difficulty change, then ship, then start the prep for the next batch for shipment 2,106 blocks later).
But they probably could never get the investment funding necessary to design and build these if they weren't pre-selling. So even though this route does leave potential profit on the table (from not mining themselves), it does allow them to not just remain in the mining hardware vendor space but to remain the leader.
Private funding allows for them to get these manufactured. less people in on the pie means bigger pie for you.
I guess we should be "thankful" they are wanting to "share" their creation(s) with all of us.