Mike
I like the 160 for several reasons. Mine opens so that the car can run at about 170-175 on the road. I turn my fans on manually when it's hot outside--and it'll stay at 185-190 in stop and go in Fresno summer heat for a good while. Obviously, if it gets too hot in stop and go--it'll keep climbing, but as Ernie suggests--the lower temp to begin with gives me more room.
10 degrees isn't going to do much to the carb mixture or
oil life or cleanliness.
Been running mine like that for quite awhile--ran my cars in the 60s and 70s the same way--no long term problems.