I use it all the time driving from AZ to the SF Bay Area. I have come to trust it for common lane changes. I think the main weakness is when a car is coming up fast in the lane you are trying to change into. I don't trust it much in that case.
I usually initiate a lane change manually, using the turn signal. I don't allow NoA to perform lane changes all by itself. Its idea of when to change is not good, and it likes to turn on the turn signal whenever it decides to change, rather than waiting for a gap first. Mostly unexpected behaviors for a human, which might alarm nearby drivers.
For SoCal, it's a little slow to actually execute the lane change. It may need a little patience from the car to the rear to let it in.
One time I really liked it was when I had to cross multiple lanes within a fraction of a mile crossing through a freeway interchange. The turn signal just stayed on and it would make the change when people left us a little less space than I would normally be comfortable with. We made it from entrance to exit while I was still trying to figure out where we were going.
Other than worrying about fast approaching cars, I have never had a problem with it turning into other cars. It does occasionally abort a change for no apparent reason. That might make you look like an idiot, but is generally harmless. You can always take over, though you'll still look indecisive.