I think this is a question that has come up on the Avsim forums, as in regards to the frame rate hits, I'm sure the program will have a option for DXT, 16bit,32bit etc etc types of texture install so that would help people with different spec systems as in regards to FPS. I currently use HiFi`s software X-Graphics and it has a massive amount of replacement textures for sky, clouds,roads,cities, water, runways,taxi etc and it does not interfere with any other addons I have like airports scenery etc. But who knows!