Thanks for the screenies and the tests, and i too am happy to hear that both have positive effects on the VR!
Yes, the specular aliasing is an expected side effect that is hard to combat by regular means. If you find it very problematic it might be possible to reduce the blendings on these areas but that would involve a bit of a coding works in the shader.
BlendFinal *= clamp( 3.f - distance(CenterPixel,(DDX(CenterPixel) + DDY(CenterPixel))/2.f) , 0.f, 1.f);
This currently the equation that i use which is my silly little attempt to quickly select the high gain specular aliased pixels, but this helps apparently to reduce the blending at these spots. You can perhaps apply this in a postprocess material too (before tonemapper) by reducing the pixel’s brightness, tho that would likely reduce the HDR ranges and you end up with an effect similar to a clamp(pixel,0,1).
If you wish to do it like a pro, try this instead: antialiasing - Fighting aliasing on specular highlights - Game Development Stack Exchange 