For my taste, silver-plated cable + Pioneer + Kef IQ would be a bit bright and forward.....but if you enjoy the way it sounds, then leave well alone; if not, get some good, cheap copper cable (Linn K20, Van Damme, Chord Silver Screen, Atlas, 79 strand etc)
If you listen to a lot of music, it may be worth experimenting with something better (by borrowing it from a dealer). Despite what the previous poster has said, I would say that this is something that you need to try out for yourself. The rears are fine with cheaper stuff, so you can experiment with the front three.