I've got ROF but not currently installed...gonna wait till I buy my new computer and start it up then. ROF is one good looking game if your computer can handle it, and from what I can gather, the support from the dev-team is more than impressive, adding new stuff at a reasonably regular basis. Apparently they're working on Photo/Reconnaissance planes with cameras and Airborne telegraph.
Given a little time, I'm sure that ROF will become the IL-2 of WWI. They already include (although you hafta buy them) airplanes I've never seen in any game before, like the Sopwith Dolphin! Who knows what they'll add to the future? D.H.9? R.E.8? Sopwith Snipe? Keep an eye on this one lads!
Otherwise, one can always take a look on Over Flanders Fields, but I refuse to touch it after our little run-in with their community some years ago...even I got principles

(And it's the CFS3 engine, so yeah, it's a MOD, not a game...)