From my perspective, the best switch engines were the Alco S-series. I worked with S-2's and occasionally S-4's (ATSF LA Terminal Division. They were the easiest for switchmen to get aboard as the front and rear handrails seemed to be what today we'd call "ergonomically designed." At least I found they were easier to work with than the FM's and Baldwins that I was on during a short stint on the C & NW in Chicago.

The Alcos had the ability to pull over 100 cars in transfers from First Street to Hobart on a daily basis. Of course the speed was about 10 mph at best when the "train" (which usually had some cabooses at the rear) was that long.