SAW
I think it depends on what you want out of a game. I personally played flight sims to gain an insight as to what it was like in WW2, and to learn about the teamwork/tactics etc. I have no interest in a game of StickJerk™, in which the object is to tweak various game and stick settings to the maximum effect and then pretend to be a "combat ace". Heck, X0847Marine said it best, many moons ago.

For these reasons, I have greatly enjoyed Silent Hunter III - exploring the underwater world of WW2 U boat crews, and the tactical decisions to be made.
I have tried that train simulator - it was fun, but not something I would want to play over and over.