It doesn't add anything to the Accu-sim aircraft - in fact, it's off by default when they're loaded. It enhances other aircraft (default, freeware, payware) mainly with sounds, also by adding some ground and water physics and some turbulence effects. I use it with the Manfred Jahn C-47 - mainly by moving the cabin integrity slider to "bucket of bolts," which gives it a nice barely-stuck-together feeling. Works nicely with TuFun's sound package. So it's good for applications like that. If you're exclusively an Accu-sim flyer, there's no point.
By completely revamping the nature and the format of the physics engine used within flight simulators, Sim physics X takes things to a whole new level and adds in several hugely important functions under one easy to manage banner, some of which have been used before in a simulator.
Picked with various functions and formats all in the one place, this gives you an all-in-one solution that you can rely upon to completely manage the physics and the performance, making the flight simulation experience more important and more realistic than it has ever been in the past, forcing you to adapt and change.
The runways have been totally modified and improved to give you an ever more realistic physics system. Now you can't just land and deal with a bumpy, damaged runway - if there is planet of damage you will notice that flying and taking off becomes more challenging 2b1af7f3a8