I've got Vue 10... the material preview is certainly very good. Here's the breakdown of how the Vue material editing system stands now:

http://www.e-onsoftware.com/products/vue/vue_10_complete/?page=10

See the last section regarding their "Smart Graph Editor"... I suspect once you get into the nitty gritty, in any more advanced system, it's going to get messy?

But I'm guessing an equivalent to the current, intermediate material mixing and layering system is what you'd be after?

EDIT: Of course Vue's system is all about materials as landscape layers... so it' a bit different I guess...