Just to clarify a bit -- although it may already be clear...
ATI sold a Radeon Mac Edition PCI card. Then, later, they released the Radeon 7000 Mac Edition PCI card. Still later, there was the Radeon 9200 PCI card.
The benchmarks Gorgonops linked shows the relative performance, plus his great discussion of the technical details.
There were "hacked" versions of the 7000 and the 9200 and if this was done right the cards work just as well as an authentic Mac Edition of the same model number. So, for example, if you decided you wanted a Radeon 7000, despite the sometimes lower performance than the original Mac Radeon, there is no reason not to get one of the $30 or $25 Sapphire Radeon 7000 cards that has been converted to Mac use. And, in fact, it has the advantage that you get 64 MB of VRAM as opposed to the 32 MB on the ATI version of the 7000.
The original post about the 7000 you linked to on Ebay was a little confusing. Don't avoid it because it's a hacked card, avoid it until you've considered the other options.
Now, in my opinion, in order to hack these cards properly, the serial Flash must be replaced with one of greater capacity. Some folks just write in edited Mac firmware, but it's missing pieces to make it fit (PC versions of the cards came with flash chips with half the capacity of the Mac version). Mostly this edited firmware works fine, but there can be issues like no display until some point in the boot process - displaying at power up is sometimes one of the things edited out for space.
I like the R7000 from Sapphire. I've used it down to 7.6.1 (without drivers) and with the acceleration drivers in 8.6 with a little work. That's after replacing the flash chip and flashing in the full Mac firmware, of course.
I get confused about flashing the 9200. Apparently there were some different versions on the PC side with lesser or greater performance but all called 9200 (some suffixes like SE) and there was a 9250 as well. If anyone knows a source that sorts that out, showing where the Mac version liesin the taxonomy, I'd love to read about it.