I have heard good things about the Coastline Cover, but I would never put it on a dirty car, and I don't want to wash my car every time I put a mask on. That's just me.
We have had the Protect-a-tow for our PT. We have towed 35K miles with it and it does its job very well. Our windshield does get dirty (very) in a rain or snowstorm. I keep a gallon of water and rinse the windshield off.
When we stop and unhook, we just roll up the Protect-a-Tow and attach it with bungees to the back of the MH. It takes no time at all to re-attach it to the car. Roll it out, attach the hooks to the two eyelets, run the bar across....done, in one minute.
You cannot turn sharp enough at speed to lose protection unless you do u turns at 60 mph
I would make the purchase again.
There are other types of skirts out there, check them out.