Having lurked here for a long time I think it is time to pay back to this wonderful community by telling my FSX story. I recently upgraded my computer yet again (i7 2600k @4.9 Ghz, Geforce 480, low timing Ram etc) to combat those dreaded blurries and stutters. I followed Nickn's advice on setting up windows 7 (much appreciated) and I used Bojote's fsx.cfg tool (again my gratitude) but I was still somewhat disappointed to say the least. I was tired and fed up with the performance cost ratio. As a last resort I decided to go against general advice from the forum and I turned on preview DX10. The result was quite frankly sensational. All stutters were eradicated instantly. I do have those DX 10 issues mentioned here (flickering, no progressive taxiway aid) but compared to what I was getting in DX9 mode, I certainly can live with the DX10 shortfalls.
Would be great to know from others here in the community if they have had similiar experience on a high end PC.