They have almost no risk of people not paying since they still have the miner in hands (and if u don't pay they could just point the miner to their own account) so the pay 6 months up front is a bit much. I agree with the contract length (6/12 months) but the full payment up front is tough when that could be close to another $10k for some of us.
I think I would sign up today if it was month to month and 6 month contract. (payment of first month today).