I agree CUE is pretty horendous, even with six months of practice. While the idrive on my '11 BMW Z4 generally was much easier to use, I wasn't happy with the nav on that either. Its awful when you have to type in addresses with the knob controller, and it frequently gave many different possible entries for the same address on an interstate, but then when you clicked on specific addresses none of them corresponded to the street number I had put in. Extremely frustrating.
That said, i feel like I'm a beta tester for CUE, and I'm finding it very frustrating to use. Thank God for the steering wheel buttons. Otherwise I might have broken down and traded it in by now and taken the loss. Been a very long time since I bought a GM and not sure I'll be stickng with GM after this.