This is a step in the right direction.

If you really want to do it right you should provide customer protection by providing refunds based on missed opportunity cost.

For example:

• HashFast promises to ship on October 30.
• Customer paid ~60 BTC for a pre-order unit.
• Customer registers a refund BTC address at the hashfast.com site.
• For every day HashFast misses their target shipping date, a partial automatic refund will be made based on what a 400 GH/s unit would have mined at the difficulty at that date.
• This would continue until either the refund is complete or the unit is delivered.

This would:

• Prevent a BFL-type pitchfork scenario and alleviate worries that HashFast might be hashing with customer hardware at customers expense.
• Give customers peace of mind; At worst they would have provided a free BTC loan to HashFast. At best they get a unit that has already started making some ROI before delivery.
• Provide a strong incentive for HashFast to deliver on time.