Sorry Chipp for late reply - not sure to proceduarl terrain as I never used them in Vue(I'm using Geo COntrol now anyway) & yes to preset atmos but no to preview window.  That said, C renders very fast - so I have not missed the preview window at all - that's just me of course....You can see the pics I've done in C here(not sure if you'll like them or not) - none have taken more than 2 hours & that is with GI/Translucency(leaves) water etc et on.

I have both both C & Vue galleries, so you be the judge.

I should add just to avoid arguements or flaming - I like both apps, but for now I find C more suitable.  I HATE the node editor in Vue - I'm lost in it, where in C the drop down format(as in Vue 4) suits me better :) Plus I like all the plugins available for C.

Both apps have the pluses & minuses.  DOuble edged sword so to speak. Can't win for loosing no matter what I say.