Nano, The latest ZL17 from simheaven incorporate HD Mesh V2, so no I don't think that could be the cause. I use photosceneries for my country, Protugal, where I do a lot of VFR flying, and I have HD Mesh wherever it is available; for both Portugal and Spain I also have w2xpl enabled. My texture deffinition is extreme, such as yours, and most other settings are about half way; I use SkyMaxx Pro, also with settings about half way. Depending on the cloud cover I can get between 23 and 60 fps flying in my country and about the same in most of Spain but if I go to European countries with a lot of mountains my fps drops, due to HD Mesh, I believe; also, as I said before, If I enable w2xpl in central Europe I must be prepared for some loading delays, even if the fps drop is not severe. Flying VFR I can usually stand the loading delays because there aren't many scenery loads during one flight, but for IFR it's absolutely unbearable