At my current course, we use the same trash cans as you do. We usually don't have any problems with them getting dented, but as far as rusty, we always lightly sand them down each winter and put a fresh coat of paint on them. With doing that, we have no problem with keeping them looking nice.
The last club I was at, we used the par aide stands with the ball washer and trashcan attachment. The actual trashcan is plastic and we never had any problems with them blowing away, besides maybe if someone didn't put the lid all the way down, but even so it never blew far. During the winter we would just wash the plastic trashcans out and then put armor-all on the outside of the trashcan to brighten up the plastic and remove any dullness of color from the sun. We would also sand down the metal stands and ball washers and put a fresh coat of paint on them if needed.
http://www.paraide.com/ParAideProducts/ ... fault.aspx^that's a link to it.