I find that although Realflight my not be identical to flying (not far off though) it helps to improve stick sense and orientation when planes in different attitudes.

I personally benefited by improving my rudder inputs when in an inverted harrier, something I've always been a bit aprehensive about doing with my real planes.

I also spent alot of time doing the rolling manoeuvres, taking off, putting some aileron trim in so it rolls on its own and just flying around using rudder and elevator.

I keep me hand in with the torque rolling occasionally. It keeps you sharp torqin the CPLR Cap or Giles!!

Find that it may not be a substitute to flying, but it definately helps......especially in England when it never stops "!@£%$ raining!!!!!