...I've been doing some homework..

I'm no
James Alfred Ewing...but the ergonomics of RailDriver are more practical than the repetitive motion of trying to control everything with a mouse and keyboard...
How many people use a keyboard & mouse without dropping there wrists down to rest whilst navigating? This is the greatest contribution toward repetitive motion injuries.
I've lately been involved into researching the config files of not only locomotives, but default and third party content on the matter of mass and product load weight.
The locomotive enginespec files are for the most part based on real world perimeters, and are pretty accurate.
However have you ever placed a loadable rail car in Surveyor along with a locomotive nearby(Quick-Drive will not work without a locomotive placed), and then go to QD, and check out the details?
The "loaded" hopper is no where near the max allowable weight of 286,000 pounds(143tons).
You then have a consist that does not cause the locomotive enginesound to work properly(authentic enginesound), let alone the performance of the loco is way more power than needed.
Researching mass weight of different freight cars and load amounts is complicated to say the least. This is one of the good points of open-end software. You can alter the performance of just about everything except the rendering engine.
And remember that mass & product weight in config.txt files is in kilograms, which must be converted from standard weight(US-America).
1 kg = 2.205lb
Standard Unit
Conversions
143 tons = 129705.215kg
Typical SD40-2@ 360,000lb. = 163265.306kg
I of course round off to the decimal point for config files.
And...so...
These are some of the factors that affect the performance of the throttle controls on a locomotive, and yes RailDriver has no "dentent" points delineated on the throttle or brake controls=you need the HUD to determine throttle position, brake application pressure & brake release pressure, just as you would in a real-time locomotive control operation.
For Diesel fans World of Trainz(payware) currently has the most complete desktop displayed in most every type of locomotive offered. The gauges operate, and most of the time I use the HUD only when I wish to know the speed limit in the block I'm operating in. Some (WofT) desktops include an accelerometer(if ordered by the particular road), that tells the increase or decrease of speed per minute. With all weights correct, this is when it gets really good! A calibrated RailDriver is really responsive to control the train.
These factors are only important to a dedicated train simulation. I'm happy if your happy.
I just wish all content offered had at least as much controller gauge feedback as the Auran Default Gen interior(kuid:-1:101475)!