I have a similar system. ARC Ref CD7, LS25 mk2 and Ref 110 amp. I have also owned a VT100 mk3 and CD3 in the past. I use Audio Research Litzlink II Balanced Interconnects between my LS25 mk2 and Ref 110 and a double run of Audio Research Litzline II between my amp and speakers. I have an old pair of Synergistic Research cables between my CD7 and LS25. I played with a number of cables including Cardas in the past but have always found the ARC to be the best match for ARC gear. Until recently it was the cable Audio Research used in house.
Excellent cable for the money and especially used as they are no longer made. My cables are 8 to 10 years old and I really believe that cables get better the more they are used.