I had about 15 minutes to check it out with a few free roams:
The first impressions are
Good news is:
The route is ABSOLUTELY beautiful! Really, really environmentally accurate.

Its unreal!
The route still runs well (for me) - framerate wise. I'm really blown away!
The gradient transitions are much, much better. They're smooth now.
The time-of-day files are much better. Color and lighting is outstanding.
The bad news (more appropriately, the "baffling news"):
The switch stands are still wrong! Huh?
Many of the curves (at least out of Truckee) still have very rough/awkward transitions into curves. The superelevation has been toned down, but its still rough going in and out of it.
The sound on the locomotives (at least the SD40s) is in dire need of an upgrade (esp. the horn). Time to reinstall the Simer4 mods.
The couplers on the Autorack cars are down below the railheads and disappear depending on the view.
I suppose I will need to verify cache if others cant replicate these issues.
Overall, i'm not complaining! Just some things that make you scratch your head...the switch stands take all of 5 minutes to correct, and are rather important, for example.