Hi, John. I have the Alaska version 20-20239-1. I haven't had any problems so far. I am running on a small spare bedroom layout using MTH Realtrax, which is cleaned once a month on a regular schedule. It runs very smooth at the slow speeds I operate at (seldom more than 15 SMPH ). The prime mover sounds are also very nice, and I also like the extended shut down with the crickets, bullfrogs and barking dog. The only minor nitpick I have is that the third exhaust stack in line doesn't smoke very well, with most of the smoke coming out of the first two stacks. I solved this by running with the third stack cover down as if the third engine is not running. Overall I am very pleased with the operation and looks of this engine, which I use to pull my Alaska work train. I bought mine used from Alan Miller, so I know it came from a good home. If you are looking for a good looking and running switcher I would recommend this engine. One thing to be aware of is even though it has four wheel trucks the minimum curve is O36. This engine does NOT like O31 (trust me on this). I hope this info helps.
On another note, I really like the vids of your layout you post here. It looks like a fun layout to run. Mike
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