My goodness, I like Valhalla cables in many applications but not here. Especially if you have speakers like WattPuppies, IMHO that would be a mismatch. Definitely additional detail, and maybe or maybe not adding brightness, but with those electronics a flatter, less organic low end I think, less rich. You have lots of speed with Halcro, but these cables would take away a bit of gestalt I think. What cables would I use? Actually maybe Synergistic Research Apex, they are a good cable, and often add just a touch of warmth and fullness to a system. Depends on your speakers though. I pretty much use Tara, but in an all MBL system, that apparently is fairly normal. Don't know how Tara would work with Halcro. The APex will give you almost the warmth of the Cardas, but with a bit more detail and a bigger soundstage I think.
Have fun,
Chris
Have fun,
Chris