Hold on there...
Two thing you should know. One The ragr 128 Works GREAT with unreal if:
a) you have enough memory >64
b) You have updated both Unreal to the 220 code
c) You have updated the apple Rage drivers.
Although this is very good, you still will get better perfomance with a voodoo2 card. Also be sure you are Using Hardware rendeing in the advanced options menu, otherwise what your seeing will look terrible.
Alex