Whether or not you can detect anything is up to you to decide. Running two runs of 14 gauge bulk cord's not that expensive. Going with biwire speaker cables is a little more expensive. If you're that curious, go ahead and give it a try. My local audio dealer suggests that a cost effective alternative to biwiring is to use a short low gauge cable run with spades as a replacement for the stock jumpers. That's what they use in their demo room instead of biwires.

I'm not all that convinced on biwiring, and I use a biwired setup. I noticed slight and subtle changes when I switched over from 16 gauge bulk cord, but nothing conclusive and definitely nothing worth obsessing about. If you're looking for a more effective way to improve the sound of your system, look into room treatments or other forms of acoustic controls. The effect that your room has on sound is much more significant than cabling.