I'm throwing my hat in with the "NOA is useless" contingent. Just did a nice long road trip for the (US) holidary weekend on beautiful, clearly marked, wide Midwestern interstate highways, in clear skies and no precipitation. NOA did not do one single useful thing for me. When NOA got it right, it was always something I could have more easily gotten right myself -- NOA just added completely unnecessary stress and jerky handling to what is actually quite an easy process.
The real problem comes when NOA gets it wrong, which it did for me (even on these ideal highways in ideal, low-traffic conditions) more than half the time. On at least half of the exits that I wasn't taking it wanted me to get into the left lane for some reason. You can stay in the right lane without taking a right-hand exit, but it apparently thinks otherwise. And worse, when I approached these exits that I was not taking, the car would slow down abruptly, which is a jarring experience and may lead to getting rear-ended in heavier traffic situations. And then, on the other side of the interchange, 100% of the time when the new traffic is merging in from the right, AP wants to center itself in what it perceives to be a very wide lane, leading to me needing to take over to avoid looking like a drunk on a holiday weekend.
So yeah, NOA for me is useless at the best of times, annoying/uncomfortable almost all the time, and dangerous far too often.