I would be seriously surprised if the Williams model looks anywhere near as good as the Lionel one. The Lionel model even blows the MTH model out of the water. If my hunch is correct, your comparison of the two would be like comparing a plastic toy to a fine brass model. Yes the better model is more expensive. I hold off judgment until I see detailed pictures of the Williams model.
The problem with Lionel is that they always ruin a great model by screwing up an otherwise perfect part of it each time they release it (GP30 rear pilot sticks out since the latest release).
See great images here ---> http://www.ebay.com/itm/Lionel...rksid=p2047675.l2557