"Useful". Depends, if you drive in DCC mode, no. If you usually drive in CAB mode, yes. Don't even have to look at the controls, I can find everything by feel and tell the throttle / brake settings by feel. All around it just feels more realistic than a keyboard or mouse. I don't have subway sims, but I do have MSTS and Railworks/Railsim.
MSTS - needs a "loader" program, and you have to exit MSTS and restart the loader program when changing from steam to diesel to electric loco types.
Railworks/Rail Simulator - also uses a loader program, which was often tempermental last time I tried it and the single lever control for the DB294 doesn't work.
Trainz - seamless interface, TRS2009, TS2010, and TS12 all use the same interface program, which loads automatically when you start any of those three versions of Trainz. Install, calibrate, forget about it, works without requiring any management at all. One problem, most steam loco specs don't work correctly with Raildriver, which is why I use the C-41 specs for all my steamers.
"don't see it being worth $100 let alone $200" - can't see that in pictures, what you have to do is get ahold of one and heft it, whack it with a ball peen hammer a few times to see how solid it is. This is not a cheap plastic toy which will break when the wind blows it off the desktop, it weighs about 5 pounds and is nearly indestructable. I bought mine back in March 2003, survived attacks from 19 grandkids and a rambunctious dog over the last 9 years, still works as good as the day I bought it.
As for the console style, I don't like modern newfangled engines either, so I customized mine with a saw and a couple of file handles.