Quick update. I am already at the 30 hour mark. Upgrade wise, I can tell you that I already reached break even. I already like the Wireworld cables better than the previous ones. So from now till full break in is all up side. Other reviews show that these cables really shine past 100h mark. So I am really excited about this upgrade now.
Everything I hear now is more controlled. Bass is flowing more naturally now. The impression something was holding back the bass is gone. Sound stage continues to improve, getting more detailed as time goes by. The highs are also improving. although I liked what I heard right away, they are getting more musical/pleasant.
At this stage I really doubt the old cables are coming back.
best,
Fabiano.