I am only fly DCS in VR! I find the bird awesome in VR! The plane gives much joy, especially vertical take off and vertical landing. I flew the bird now for 30 minutes or so. FPS drops flying above the city. Besides that it was good too fly for me. The Harrier is more FPS demanding then the rest of the planes, but WIP and i am sure Razbam will optimize it.
Don't forget 2.5 is around the corner (There was sombody that said that 2.5 had better FPS then 1.5.7) and Vulcan Api is in the planning! This will give a huge boost to our FPS. :D