One of the major differences between the 70 size of the Spectra and DCM machines is that the DCM machines are direct drive - no belts or chains. In the long run, this is going to mean the DCM machiness will be easier to maintain.
The DCM 70 (capacity 70lbs), while more expensive than the Spectra 70 (capacity 60lbs), does offer the option of the rapid refiner (temperature control) and the ability to add pneumatic pistons to the grinding wheels which offer more precise and repeatable control over pressure. These two options, while increasing the purchase price of the DCM 70 should lead to a) shorter batch times and b) more repeatable, consistent results. For these two reasons alone I would favor the DCM over the Spectra if you can make your budget stretch.
While I can't get a discount for you, I can make a referral to the people at DCM if you think it would help. Are you in the US?