I think the Steinbrenner book ("American Locomotive Company: A Centennial History" or something like that) has a fair bit of the information. It's narrative history, not tables and charts, but I think it covers most if not all major steam orders from the 1920s and 1930s, and has some discussion of the locomotives' subsequent history. Most 3-cylinder locomotives in the U.S. were maintenance bears, stored at every traffic downturn, often re-built as 2-cylinder: the Union Pacific was perhaps the most successful operator (the 4-12-2 fleet were 3-cylinder): I've seen it suggested that this was because they were stuck with a whole fleet and so HAD to learn how to maintain them. Probably worth noting that they replaced the Gresley conjugating gear on one with a third set of Walschaerts: I doubt they would have tried the experiment if they thought the locomotives were great in as-built condition.
New Haven also had a fair number of 3-cylinder locomotives, and learned to live w3ith them. Not sure who built theirs: the New Haven was a good Baldwin customer in steam...
It's been a while since I visited number 60000 in the Franklin Institute. Didn't (doesn't) it have a non-standard boiler -- semi-water-tube design, pressure 300+ pounds -- as well as three cylinders? That woulkd have been another strike against it: very few U.S. railroads tolerated water-tube fireboxes (B&O under Emerson had a vew, but switched back to conventional boiler design on its last steam).
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It's interesting that British and French railroads had lots of 3-cylinder steam locomotives, assigning them to their fastest trains. Possible explanations: (i) their locomotives were much lighter than American, so maybe had less robust frames, so needed to minimize the forces of individual pistons, (ii) maybe even in the early 20th C their labor costs were lower so they could absorb the maintenance hassles more easily-- possible soupporting evidence on the second hypothesis is that post-WW II, British Rail built mainly 2-cylinder steam (only one of the BR "standard" designs was 3-cylinder, and only one unit was built of that design), and by the end of steam (late 1960s) the French were depending more and more on 2-cylinder power: some of their last regular steam runs were handled by 141R locomotives built you-know-where!
