Yes, it looks like it is a 040@25mHz & 160mHz 603 PPC which is the slowest version available, but these cards are pretty hard to find working, specially with the BVision card. You could wait for a better card for a while, depends on how fast you want to get one.
As for the difference between the BVision and a Voodoo card, max RAM on a BVision is 8mb and you can go up to 64mb w/a Voodoo, but then you also need a PCI slot adapter like the Mediator or such.
Depends on what you want to do and how soon you want to do it.
