Can you actually get the machine from bitmain, though? They usually sell out their pre-orders in minutes. If you've ever wondered why, it's because some people have done enough business with them that they can just make a phone call and pre-order the pre-order, leaving scraps for individual retail buyers...
I can assure you, Bitmain does not allow large customers (at least not from the US) to have access or knowledge of preorders before everyone else. We do a lot of business through Bitmain, but have never been able to get special treatment. If you have info that says otherwise, please let me know - I'd love to get special treatment
