I second Ed's statement about CSX. Anywhere I've ever seen them for around the last ten years, they were in a yard being used for local service in medium cities (Mobile, Ala, Dothan, Ala, Pensacola, FL, Montgomery, Ala).
They were usually filthy and look terribly rusty. I think CSX policy was to use them in this kind of service until they had a catastrophic failure. Then, when that happened, it was off to the scrapper or secondary market. They were not to be rebuilt the way EMDs were.