Let me pour some gas on the fire...
Black Arrow will start shortly taking preorders and offers 25% discount on all preorders paid in September and October. Today, using the 25% discount, one can buy a Prospero X-1 for $239 and Prospero X-3 for $3999.
Let's start with $4k for 2 TH/s if someone ordered earliest. They promised matching performance. Current performance is about $.4/ghps. That means they have promised to ship at least 10 TH/s per order (more for people who paid more than $4k). That's not even counting the fact that the Prospero is hugely power inefficient and most hosting would cost more than the income generated by even turning it on.