With apologies to Eddie G who started this thread it should be noted the K-Line Hudson while having some fine detail is also the most underpowered of all the versions posted here. Mine nearly overheated pulling 5 18" K-Line heavyweights. As posted above they can burn up motors with relatively modest loads. OTOH the newer Lionel Hudsons including both J3a's and Vision Hudson don't break a sweat with a dozen cars.
All depends what you want to do with an engine. Admire it on the shelf or use it to pull prototypical length trains.
Pete