FireGL and Radeon cards use the same chips, the only difference is in the software (FireGL drivers are optimized for CAD applications rather than games).As much as I like AMD, they really haven't been able to match Intel, from what I've seen so far, maybe in a lower end iMac. What I would really like to see is a FireGL option for CAD, since they make a mobile chip as well.
I don't know if this is still true today, but a few years back it was possible to modify FireGL drivers so they worked with normal Radeon cards (same for GeForce and Quadro on the nVidia side).