Well, to get back on track, here is another pesky opinion: I believe most folks in 2- rail scale regard plastic as cheap, no matter how much it costs or how detailed it is.
The 3-rail crowd likes plastic Diesels, but cannot have a steam or electric model in anything but die cast.
So, in my opinion, the only truly scale plastic will be, like the 3rd Rail E-7, aimed primarily at the 3-rail scale folks, and 2-railers will have to suffer the compromises.
Again - just opinion.