They suck!!! At least for my laptop's ATI card. Radeon open source driver kicks the snot out of it but you need to download the radeon firmware for it to work proper on some cards, including this one.
I know I am a thread reaver on this one, but my opinion stands strong for a reference to others. The open source driver has come a long way in acceleration, without the bugs(new version=new bugs) and breakage from kernel/X upgrades that fglrx puts you through. Glad I am done with it