Hey I just got my Revzilla Yellow C3!
and it FITS! perfectly!!
Concerning the water getting through the top of the visor. I devised a very simple test. Since water vapor (fog aka my horrible breath) is basically rain but in a smaller scale. It will get through any gaps and it will show on the inside of the visor.
So what you do is first make sure the visor is completely shut. Then get nice and personal with your C3. Place your mouth on the upper cornerof the closed visor and slowely breath on it. It will fog up the visor. If the seal fails . The opposite (far) side of the visor will fog. Thus displaying the location of the gap in the seal. Just repeat this along the top of the visor to the other side.
See, its just that easy. If the fog gets past the seal then rain will too.