The steel is a decent gauge, but the solder joints, in my experience, are pretty fragile. Lionel seems a consistently sturdy product, Flyer and Ives a bit less so. As far as locos go, AF and Ives stuck with cast iron much longer than the guys in New Jersey, so their stuff is much less likely to survive a drop on the floor.
When you look at 1930s-era Lionel tinplate rolling stock, I think that stuff was dipped in paint rather than a spray or brush paint application. Lionel’s paint seems quite a bit heavier, therefore more durable. The other guys, not so much. Some Flyer stuff loses half it’s paint over the years, especially if handled without much care or packed poorly. What’s weird is it seems dependent on the piece. Flyer prewar tank cars seem to suffer a lot of paint loss, box cars and gondolas fare much better.
I don’t know, environment means a lot. I see dealers drag stuff show-to-show with cars just piled in a box, lurching around, unpack, repack...ugh, it’s like carrying stuff around in a rock tumbler
