MSTS through the years had a dedicated band of users who helped improve the sim as time went on for all the rest of us, plus some add-on creators that made it super good.
With RW upgrading/updating to now TS2012 (RW3) by the RS.com team, then you know you're working with a improving product - constantly.
One disadvantage, we can't go back to the old product, unless of course, we do not connect to the internet, myself, would rather they update often.
Physics for RW is simply horrible, imagine climbing Cajon's 4%, stop, and back up the train, uncoupling while engines are braking...you should expect the consist to continue, even accelerate, nope, it stops eventually on a downgrade no less.
With MSTS years ago, pushing with a little SW1200 CB&Q 3 boxcars in a yard, uncouple and brake hard, the 3 cars glided down the yard track into other parked boxcars, causing one to jump the tracks on impact. The standing box cars in question, were 3/4 a mile away. RS.com folks need Derek, hands down.
And yes, newer RS.com releases the freight/passenger cars physics are improving, the defaults, not yet. Amazes me that the developers out with add-on's don't improve the physics, which tells me that its the computer code internally, and is (way) off.
Horns are created by an outside contractor to RS.com, an English firm. Rather difficult for them to acquire U. S. Rail roads sounds.
Their are individual improvements available at the various sites, i.e., Railworks America just to name one, trainsim.com is another.
This product was unveiled in early 2008, slightly over 3 years later, improvements are being made, unlike MSTS, only one update was available, in 11 years, we should be thankful, but keep your suggestions going (rant if you will) on the forums, you can bet, RS.com is reading, and prioritizing almost daily.