In flight simulation, detail is everything. Aircraft performance is paramount, but things have to look right too.
X-Plane: Instruments are almost identical in most aircraft, unless customized. Alternate views include fighter-jet-like head-up displays.
Microsoft: Instrument panels are designed to look as they would appear in the real aircraft, down to the style of dials and switches.
X-Plane: X-Plane's aircraft exteriors are crisply defined, and the perspective-alteration controls are intuitive and variable.
Microsoft: Exteriors are well rendered, but perspective controls are uneven--the chase-plane option results in
a disorienting roller-coaster effect.
X-Plane: X-Plane uses geographic data to model worldwide scenery. Weather systems are more definable, and the views more appealing.
Microsoft: Flight Simulator offers more accurate snow and water placement and more sophisticated urban environments and airports.