Trucks & Wheels
Rock City Railroad
Some trucks derail much easier than others. I think low flange trucks are made for code 83 or code 70 track, but if you have 100 code track, a higher flange derails less often. As far as rolling easy, which is important I guess, Kato makes great trucks.
I've got some of those antique trucks with metal and springs, but they derail easy for some reason. I'm not an expert on these things.