Cos D1 V2 / Denafrips Terminator DAC

If you haven't already done so, check out the Srajan Ebaen/6moons Blue Moon awarded review of the Terminator. I'm going off memory, but I believe he does have some comparative information vs other DACs including the COS. He found the Terminator's 'sound' to be more in line with that of the Aqua Formula.

All the best with your considerations and choice.

Mike Powell had both to compare. He is OCD hi-fi guy on You Tube. 
Shoot him an email. He should give you some answers.

He also makes Verrastar ribbon cables.