I have used the the Radeon 9500 with the firegl driver hack (enables the workstation features on the graphics chip, wich is the same as the chip for the firegl series)
I used it with a dual screen setup, and it worked ok to some extent. I had issues with it when the model window spanned over both screens, but was ok when I had the model window restricted to only my right screen. I kept the feature manager bar on my left screen and, also all the toolbars.
I ran solidworks in 1280x1024x32 on both screens (I have a lcd screen), an also with 6x antialiasing, wich is really great because it feels more like working on 2048x1536.
I also had some issues with it that seemed related to the number of windows/parts/assemblys I had opened (low performance in the later opened windows, guess from number 4 or something).
I think the issues are driver related, and I guess ATI is going to fix it in the future.
I had superb performance as long as I did not open to many things. The size of the assemblys where quite large.
if you go for this soulution you are getting a really good "bang" for your buck performance wise, but as mentioned above I had some issues.
The best cards in this series would be the 9700 and 9800, I would not bother with the pro versions for the 9500 or 9700.
They are only slightly higher clocked versions.
Bonus: these are good gaming cards as well.
Good luck.