The Linux catalyst driver is still supported and maintained as well as long as you are using a supported distro (kernel and xorg version). It's the same as on windows. The only difference is that windows doesn't change the kernel and display server as often as Linux distros do.
The problem is that no major distro uses both the last supported Xorg and Kernel version.
This model of Catalyst Legacy releases is not working for Linux.
The problem is that no major distro uses both the last supported Xorg and Kernel version. Not even the long term support Ubuntu 12.04 LTS.
It does, though as of 12.04.2 they backported the Quantal X server/kernel and use them by default on new installations (at least on 64 bit). I guess it's related to UEFI. Kernel 3.2 and X server 1.11 are still in the repo, and the xorg-edgers PPA has X server 1.12.
openSUSE 12.2 runs kernel 3.4 and X server 1.12. Still supported and poised to become the next Evergreen.
SwapbuffersWait basically stalls the GPU until buffers can be copied without tearing. It is always used for non-fullscreen windows, even if vsync is disabled, and as such it can have a huge effect on performance. It should always be disabled for benchmarking.
Personally, I just keep it disabled and live with a little bit of rare tearing, in exchange for much smoother overall performance.