With the exception of liars, seems a good gauge of the results.
Lying to exit pollsters can be interesting. In 2016 as I was getting into my truck I was exit polled and asked who I had voted for. I answered Hillery. The guy looked at me and after a moment he frowned and said “Well dressed guy, expensive watch, new GMC Denali truck, not the typical Hillery voter ... you wouldn’t be pulling my leg would you?” I climbed in, started the truck, rolled down the window and said “Excuse me, I’m holding this parking spot for another Trump voter.”
Not sure what he wrote down ...