Perhaps I should have posted my question this way....
If my DAP has the option to play in balanced mode would it make an audible difference to warrant an extra $150.00 for cables?
My gut feeling is that unless your device has an inherent engineering flaw, a simple "no" would be the answer since, from my experience, balanced cables only cut down on hum and noise pickup under long distance runs at very low levels.
But, from the way this thread is going, I think you want a definitive answer to counter that which you've been told at head-fi. So, who you gonna believe? Who do you WANT to believe?
The only way to get that elusive truth is to try it for yourself and see what your own ears tell you. Buy the cables from someplace that will let you return them if the difference isn't all you're expecting and try it for yourself.
Let us know how it works out for you.