That makes it a no deal for me

There is no way that they will deliver before 15 March, this means a refund or more hashing power for the same price.
No extra power means no profit.
Delivery after 2014-03-02 means no profit.
It depends on the hash power you order. As much hashpower you have and as soon as possible you can use it to mine, the more lucrative it is. For my 300 example, I'm getting about 100% ROI.