I await the arrival of my sound fitted version but when it arrives I will still run it in. I know Dapol say this is not necessary but I guess they mean the motor. My thinking is that any mass produced 00 scale loco is likely to have varying tolerances in the gear train with attendant high spots/stiffness.
I have a Bachmann pannier which now runs beautifully but only after a year of “running in” including a trip back to Bachmann so if my Mogul does not run super smooth straight out of the box I will not throw my toys out of the pram. As far as I am concerned it is a beautiful model and I