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).
always treat iOS device better, yes i love iOS, but please .. i want iMac refresh, current iMac almost beaten by new MBP in terms of processing power