I'm experiencing the same issue many others have reported - when not using Bluetooth, the person on the other end reports that my voice is choppy, or in one case, "sounds like you're in a tunnel".
Moto has released an update that may fix this, but VZW has not yet released it; I'm not sure if I want to take the chance that it will actually fix the problem.
I still have about 10 days left in my 14-day return window, will I be able to return the Moto X and reactivate my old phone until/if the update is released and checks out? I'm really hoping the update comes out before I have to make the decision.