Been a long time user of X-Plane 10 and running it on a beast of a system and also using Real Terra Haze, Skymax and Reshade. Trust me, Outerra's rendering engine is leagues above XP10s. Real time atmospheric scattering, AO and ton of other things which gives the whole environment a very realistic feel that can't be achieved in X-plane 10 at the moment. Take a look at this video
Notice how realistic the A380 looks in this video. That is because of how the light interacts with the aircraft surfaces. No need to bake textures anymore because everything is handled by the Sim's engine.