Your view is definitely from a railfan's point of view. Having spent the equivalent of many straight weeks ridding on SD-40s I am glad to see them far and few between. They would wear a person down with their cramped, loud, hot, dirty, smelly, cold, and bone rattling vibrations. I always felt the worst after spending 12 hours on one. Any enthusiasm I had about going to work was obliterated as soon as I heard that an SD-40 would be on the point. The ones that weren't about to break down pulled good but so do newer locomotives.