Tyll Hertsens, who introduced the dual 3-pin XLR have kind of publicly asked forgiveness from headfidom for doing so. 4-pin will serve you just as good. http://www.innerfidelity.com/content/canjam-rmaf-2014-showstopper-sonys-proposed-new-industry-standard-headphone-plugs
What do you mean "basically"? Is there any crackling, noise etc? Most common problem is just dust and corrosion on the internal switches blocking the electrons from moving freely. Electrons do not like that and refuses to move. Spray some cleaner, like Caig Deoxit D5 in there - it is all open, it seems :)
That's why TNT is bringing me some cables as we speak. But seriously I do not expect much of a differencedifference, punit seems to support this expectation. A true balanced amplifier having to give unbalanced output requires more compromises than converting from voltage to current signal.