   SetFVF vs SetVertexDeclaration
  The SetFVF and SetVertexDeclaration are alternative?Is SetVertexDeclaration better than SetFVF in using Shader and in performance?   
  SetVertexDeclaration will give you much more flexibility, and is very similar to what D3D10 uses (FVF is gone in D3D10).  I don't see any reason for why you would need to stick with FVF if you're using a shader-based approach.   ;  Thank you,MJP.;  Remember, the FVF system it's considered by Direct3D9 only if device's vertex declaration is NULL   