I've not tried it on every US route, but it's working very well in my book. Good job!
I've noticed something weird about Railworks with my laptop's sound chip that may also happen with desktop sound cards. If so, then it's Railworks and not my laptop. Here's an example....
Using the consist builder, I made a 7,000ft train. I used all ES44ACs. 3 on the head, 2 at mid-train and 1 on the rear. These are all Krellnut's helper locos from his ES44 10-pack of sound files. That means each loco I assigned had it's own unique sound file. This not only avoids the flanging jet sound effect, but simulates real world engines of different ages and states of wear on it's parts. That manifests itself as each loco having a slightly unique engine sound as a result. Hence 10 different real world locos sampled for the pack. Plus his wagon pack sounds are in effect as well.
So I load up the train in a route. Now I pop the camera to track side in free roam mode so I can sit and watch the whole train go by. I start the train up and as it passes, I hear the head engines just fine. I also hear the cars after it fine. No problems so far. Then as my mid-train helpers are approaching, they are dead quiet. Then just when they are about 1-2 cars from me, their sound jarringly POPS into existence. The same thing happens with the last loco on the end as it approaches.
But what I noticed was from that point on, they are fine. Meaning... they volume fade up into existence like they should in real life as they approach. It's like the sounds need to be triggered once (being very close to the loco to trigger it's sound) before they have proper fade-ins from then on out in that session. I learned to just pop instantly to the end of the train real quick before throttling up the train just to get it's triggering out of the way and it fades-in from jump.
Not a problem for the front locos since the camera starts there by default and they are triggered instantly as a result. I just wait for the mid-train helpers to jarringly pop in once as they pass since instantly popping to the mid-train helpers isn't possible and I'm not gonna advance the camera 3500ft to do so. Then it's smooth sailing sound-wise from then on. It's the same with default locos. Very weird quirk!
