The k line cars are a good match..not perfect but way closer than MTH which are too light. The problem is they're hard to find and you'll likely pay way more than list..
Joe, do you have some photos or are you only speaking from memory of someone else's cars?
Albert - Not sure. People have said the darker models are more accurate, but that would make the lighter GGD cars inaccurate, which would be surprising.
A friend has them.. I clearly remember him going through the same thing you are.. I'll try to get him to email a photo.. .. From what i remember the difference in the color wasn't much off and the striping was very much on.. I know the cars were 18" And beautifully detailed in and out... The MTH cars/ engine are way lighter
I owned the 38 GGD set for a short while until I returned it due to problems and was obsessed about the color match between locos and cars. The Lionel engine is darker than the cars. The latter MTH is too. (Early one was comically light.) THe Lionel Dreyfuss is a superior model design over the MTH. THe MTH has incorrect proportions in that the front seems to be a slightly smaller scale than the rear.
The prob with the Lionel is that the smoke unit is an old piston puffer. I am sure it can be replaced, and I may do it. Supposedly the Lionel/Smithsonian cars and engine were based on actual paint samples. My guess is that the production Lionel Dreyfuss was a close match.
Praying that Lionel gets it act together and issues a Legacy or Vision Dreyfuss. I am sure it will be awesome.
