I was using cheap RCA cables WAY
back with success and see no reason to switch.

Well, there are legitimate reasons to use quality cables for audio and
video, just no legitimate reason to charge what Monster Cable and
similar companies charge. Radio Shack cables are junk and *do* degrade
your sound/picture, but interconects at an equal or similar quality
level to Monster, et al., are readily available for half the price or
less.