Mine tend to be extremely erratic.
I'll just be sitting still in my garage and it'll beep a warning and then go away, then beep a warning again but closer, and continually do that with nothing moving or changing distances.
On top of that, I'll randomly see my passenger side mirror correct its position upon startup as if it hadn't gone back to the correct spot after reversing during the prior drive.
Not to mention my audio system randomly either won't show track/song info updates or will just be blank for the entirety of the drive and will have to be powered off and back on to get it going again.
These cars definitely have random issues. It is annoying, but it's not enough to ruin my drive or the overall experience. Usually that is ruined by other assholes on the road.