I think that the size of the card is a valid issue, it won't fit in my case for sure, and I'm sure other people will have the same problem.
Soccerman-
First I want to say that with the exception of the physical size, I don't see a problem with using four chips by itself, but it isn't wise from a business standpoint and it wastes RAM space(textures need to be stored x4).
The more concerning problem-
1 V3 ~= 1 TNT2
2 VSA-100 ~= 1 GF2
4 VSA-100 ~= 1 GF2U
Where does it stop? I hope 3dfx can get back on the ball, but they alread are at the point where the boards are not capable of fitting into certain cases, an eight chip Rampage to compete with NV2X, Radeon2, and G800 would be a serious problem. I don't think that will happen, but that is the direction they have been heading in.