Are balanced interconnects usually better?

I just replaced my amp with the Bel Canto EVO 200.2 which accomodates balanced interconnects. Previously, I used MIT RCA interconnects which I probably bought for about $150.00 for the pair to connect my amp and Conrad Johnson PV12 preamp. I see that Signal Cables are very reasonably priced and favorably commented upon and I'm wondering if I should replace the unbalanced cables with Signal balanced ones? Are balanced cables usually better? Can you really tell the difference? Any thoughts?