I honestly prefer FlightGear Flight Simulator.
Although its graphical capability can't match the Flight Simulator X, X-Plane Series, and the new Lockheed Martin Prepar 3D. One thing I love about it is the community the community is engaging believe it or not the game is completely free (unless you purchased it on CD). So lets go back to the community well the community is the developers itself they're working together on making the game better I believe new versions goes up every 4-6 months.
Although a lot of aircraft lacks realism there the game is still fun to play even of its simplicity.