First let me say that I don’t own any of the specific locos mentioned by the OP, most are way outside my era and I have no interest in them.
I am really only responding to this thread for two reasons - to remind or suggest that judging a whole poduct line by one, or even two or three products that you had a probelm with is likely a foolish move.
Every company in this business makes a few items they could have a done a little better with.
And most all of them make some really great stuff that is perfect, and a lot of the rest is somewhere in between.
Now for my rant - these are models, highly detailed scale models in 1/87 scale. That is small, they are delicate. If that is a problem maybe you need bigger toys, like those made in O gauge by MTH and Lionel.
I get so tired of these complaints on here - “I touched it and it broke”, that’s funny, I’ve been at this since I was twelve years old, for 40 years now, and on the few occasions I have broke something, I knew every time it was my fault, not the model’s fault.
Diesel hand rails are not to be touched by ham fisted giants from the nether world. Again, if you need rugged toys, check out MTH. I have no problems with the plastic hand rails on my Proto2000 GP7’s or my Athearn RS units, or my SD9’s.
I have a number of Athearn Genesis F units, far and away the most detailed F unit ever made in HO scale - I wold not change one thing about them to make them more “durable”. And none of the trucks have fallen off any of them.
After we have come so far in model quality and detail, it would be a shame to “dumb down” the hobby to make the models more “rugged” and/or “handling friendly”. It would be like going backwards to days of the no detail Varney F3 or Mantua Mikado - find some of those, there are no details to break off.
These models are intended to be run and looked at, not handled any more than necessary.
But that’s just my view, what do I know…
Sheldon