Just introduced a set of Sterling Black Mamba speaker cables into my system in place of QED Micro (shudder) and wow! I am using a Fatman I-tube amp and BC (before cables) I thought everything was a little thin and bass-light/bright. These cables have opened everything out very nicely thank you, and the bass is more to the expected level, nothing out of hand of course.
Probably old news to the great and good of the 'Wam but I thought I'd share my positive experience. The bargain upgrade bug may have bitten in the grand manner!