a couple times, but have yet to complain about balls and strikes. I have asked for a couple reviews, but haven't gotten mad.
I have attended hundred of other games and have gotten one warning from an ump from another coach stealing a bat because he thought it was illegal and told the coach to learn the rules.
Also, with only one ump if the ball beats the runner on a steal it is always an out. Nobody should complain.
I have seen some people embarrass themselves. My older son umpires now and the second a coach complains about a zone he gives them a warning. I hope i'm there the first time he tosses somebody.