After a few months with my Mojave and the auto-dimming mirror, I find it is almost ok. It is better than others that I have had but that is probably because I am up higher in this vehicle.
The bigger problem is that so many trucks (and SUVS) in my area are extreme lifted or carolina-squatted. Fortunately, I don't drive at night that much. If that changes, I will consider changing out to a manual mirror, or adding a darker tint to the rear window.
Well I guess I'm not very sensitive to it. I've had my gladiator almost a year now, and sitting in my office right now I cant for the life of me remember if I have auto dim or not. If I have manual I guess that doesn't bother me, and if I have the auto dim I guess it works well lol.