Sorry if this is late, but I have had a KRC-3 for around seven years or so, though four years of that the pre has been boxed (unused). It has been up and running for more a couple of years now though, feeding an Aragon 8008BB. Since the KRC-3 has no power switch, I have always just leave it on, turning the volume all the way down when not in use.
I own and can recommend the Arye CX-7 CD player (not yet Evolutioned). I was previously running the CX-7 and KRC-3 with MIT Z Cord II power cords, with an LAT International AC 2 cord feeding the 8008BB amp. I purchased three of the promotional Shunyata Snakebite power cords, and now use them on an AudioPrism power strip, KRC-3 and 8008BB. I switched the LAT power cord to the CX-7. This works better than my previous power cord setup.
Like others, I have tried many different interconnect and speaker cables. Much depends on what you are seeking. I think I am searching for an accurate reproduction (within reason) of what is on the source CD, with no added distortions or noise, etc. I am using and like a balanced pair of Straight Wire Serenade between the CX-7 and KRC-3. It is not anywhere near the most expensive cable I have tried there (it retails for $350 per meter pair), but works very well. My dealer thinks I would prefer the Virtuoso R (or whatver the current letter designation is), but I have not tried it.
I did try the Virtuoso R speaker cable, internally biwired, and it is the only cable that has significantly bested my resident MIT MH-750 biwire in all areas. I have also tried an internally biwired set of Serenade speaker cables, and although it was very good, easily besting the MITs in many areas of performance (treble, midrange, tone, timbre, neutrality too I think), I thought it a little weak in the very bottom of the range. Maybe it was just neutral there, but I doubt it. More likely is that I would need a double run (shotgun) of the Serenades to my speakers instead of an internally biwired run.