Well, normally, there should be no reason to use a VSA-100 based driver on a Voodoo3...
Note that there's also no guarantee that all this will work 100% at all.
Improvements.... Well really nothing certain, it might help in places where no Voodoo3 Driver works correctly.
Overall, it isn't recommended (a native Voodoo3 Driver should be a better choice).
Honestly, I don't have any special Voodoo4/5 Driver I could recommend for a Voodoo3.
Try the 1.04.00 and 1.04.01beta, as well as the x3dfx and AmigaMerlin releases...
But be sure to know what to do if this screws up your System, which is possible
Greetings
FalconFly