Changing power conditioner stock power cord

If you think it will improve the sound, it will.

John is right on.

(And Narrod is way off -- contrary to what he might think without having tried it, these things *can* be heard by careful listeners who don't believe in fairy dust).

However, as far as changing cords on the ExactPower in particular goes, when I change the cord on mine I don't hear quite as much of a difference as when changing cords on individual components which follow the ExactPower. This makes sense to me given what the EP is supposed to accomplish, but I still do find it worthwhile to use an upgraded PC here, and different aftermarket PCs do lend a different overall system sound, with some being better than others.

I could easily tell the difference between power cords I tried from Shunyata Hydra to the wall.

I completely agree with John on this. Change will happen, but is it for the better or worst, it's only for you to decide. You will have to try it.
Is you Exact Power a conditioner or a re-generator?

Narrod, very good comment. Do you have closed captioning turned on when you watch TV?

Audphile1: The Exact Power is a regenerator of sorts (it doesn't regenerate the entire AC waveform, but more efficiently compares it against a fixed internal reference using a sub-cycle feedforward technique and then compensates for distortions and voltage deviations by actively regenerating whatever's required to make the summed output correct, which is feasible because the desired output is constant).

Zaikesman, Exact Power makes 4 models. Actually one of them is a filter, model is called "UltraPure".
Which one are we talking about here?