It seems dropping my cloud textures down to 512x512 is the only bearable solution which sucks. Even with 1024x1024 res clouds and todays wx in Auckland (grey and rainy), my FPS were hovering around 6 - 14!

With 40km vis and a few CU I usually get a solid 30FPS.
Any more ideas? REX are realllll slow at answering customer support in their forum.