Various Materials And Longevity.

[Mountain Goat]

I have the odd loco in which is said to have had issues but I've found no issues. The version I had isalatet one so maybe I've been lucky. I did have one loco where the chassis was very tight in the body which I believe to be the way the chassis was cast. I filed off the excess (Very little) and it was OK. Though I have hardly used it or looked at it, when I first heard of such issues I brought it out to check it and it was fine. It is difficult to know what to look for unless one has had issues.
I was tempted to sell every mazak model I owned but then I thought I was being silly!