@rossb OK my experience was like yours. It sucked. Returned it! Soundstage was collapsed, no depth, no air. Picking up a Denafrips Pontus II this evening...
Congratulations on having good hearing and good taste.
Good that you could return it. These things don't improve with running in. I ran mine in for hundreds of hours and it never improved. I ended up having to sell it at a loss.
Not familiar with the Denafrips but from reviews it should be much better.
Just goes to show that "measurements" are not the full story.
And to answer your original question, I recommend Furutech TCS21 and TCS31 as excellent sounding and excellent value power cables (I use both).

