We full-time, and have a Pinnacle washer and Pinnacle dryer in our trailer. The washing machine is great. The dryer takes a while as it is only 110V, but it works well too. We would not be without them.
One of the places we stayed was at a KOA in Salt Lake City. Great people, great park. 1/2 is a KOA, the other is long-term. They have a laundromat on the long-term side. They are on North Temple on the W side of town. There are a lot of homeless in the area.
They did a great job keeping the laundromat clean, but it was right by the street and anyone could walk in. I went in there a few times to wash a comforter that didn't fit in our washing machine while we were there.
It smelled like urine once - but I think it was one of the people in there rather than the place or a machine. There were some "interesting" characters there a couple of times. Check the dryer for gum (opened one that had some very fresh gum in it), but aside from that didn't have any real issues there. The machines were clean, but I tended to try to go in the morning just after their cleaning folks had been in there. I tended to use a larger machine that cost a bit more and seemed less used.
There was a great big laundry down the street. Their sign advertised that tour buses were welcome. There was either a stabbing or shooting there during our stay that made the news, and you saw police there a lot when driving by. Any laundromat can have issues. I lived in an apartment complex that had their own that was restricted to residents only. They had gum in the dryers from time to time too.
If you can have your own, that's best in my book. If not, take a look around and keep your eyes open and your mind on where you are. You'll know pretty quickly if you should be there.