I for one wouldn't mind quality RW conversions of some *or even all* off the USA stuff I see on those MSTS pages like at 3dtrainstuff.com and elsewhere.
I hope RSC's Cab Forward, combined with an updated Donner Pass, are one step in the right direction. If the announced SD45, F40 and Sherman Hill are quality assured and well accepted by us - the community of buyers - perhaps there will come more third party USA stuff to Railworks. ... one sheep over the dam, etc.
While there are glitches with the Cab Forward and sounds sound a bit lame to many of us, I really enjoy the engine and think it was well worth buying, even at full price.
Those small modelling errors are easily corrected, and a new soundpack is also within reach. Sounds are a bit of a personal preference in the first place and will probably never satisfy everybody.
Sound packs should be captured off a real, live engine by a professional, which in the case of the Cab Forward is out of the question as none are in operation. So the sounds either have to be captured off old film, "guesstimated" off other live steam engines or completely synthesized.
The sounds I miss the most are the roar of the burners inside the firebox, including the "poof" when the main burners are ignited. I once watched an oil fired DB Class 01.10 express passenger 4-6-2 on an excursion and noticed this "poof" which even had a burst of fire coming down into the "ahspan" when the driver was preparing for departure. This is an effect that - when prototypical to the Cab Forward - can easily be implemented using the "stoker" and "firedoor" controllers.