I have been using a Voodoo4 and it's been working identical to the Voodoo3 right down to the Mediator driver bugs

. My tests show it to be nearly the same speed as the Voodoo3. The advantage is twice the gfx memory, a little sharper image quality, and a few more display modes. I'm going to try and get the large texture support for Voodoo4+ (greater than 256x256) going in Warp3D as well as more bug fixes and speed-ups.