Yes, very much so.
A lot of people don't realize that quarter panel rust, a lot of times, is caused by minute paint chips caused by rocks. So small you really can't see them for a long time, but they are there. Some quarter panel rust is caused by the inside, but most is caused by chips on the outside.
When I buy used, I look for little things like that. If a person trys to keep up their vehicle in some kind of shape, little things like mud guards, undercoating, etc... are all signs of somebody that cares about their vehicles.
Another thing to think about, is state laws and liability. When I drove professionally, I talked with other truckers and they told me about incidents where they were liable for cracked windshields, due to mudflaps that were missing, or broken, etc. Because the driver of the car got pictures of a mudflap missing, their insurance went after the trucker. The best one I heard of, was a guy that went after a trucker because the truck threw up a rock and cracked the windshield. Investigation by the Highway Patrol determined that all mudflaps were in place, in good shape, so he walked over and gave the car driver a ticket for following too close. hahahaha Don't know how true the stories were, but that one was funny.