IMO graphics are what matters. Sure you can have all of your airplane models PMDG quality with all systems and performance simulated, but how many simmers are actually going to use the model to its full potential? I personally, like to feel as if I were within the sim, to make the surroundings look as real as possible. If graphics didn't matter more than flight model then you'd be flying a T7 depicted as a horizontal cylinder flying over miles of poorly constructed terrain... but then again your flight sim 777 flies exactly like a real world 777 would.