Good morning. I am running a Krell FPB300cx thru a Krell KCT and asked my self the same question. I originally was running a KRC-2 pre and had the chance to upgrade to the KCT. Initially running the KCT thru CAST I felt the bass was a bit lean compared to the KRC2, which seems contrary to what others have noted. I switched back to the XLR connection using a Cardas Quadlink and an still analyzing the sound. I may try the KRC2 again soon and compare once more. I don't feel the sound is that much different between the CAST vs XLR but it will take a bit more evualuation I believe. All in all in my opinion not a night & day difference. The XLR with the Cardas Quadlink works great with my system. Give it a shot and see what your opinion is. I would like to hear your outcome.
Good luck, John
Good luck, John