Well here are some quick results from me.
158.16
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3DMark06 - 8660
158.19
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3DMark06 - 8662
158.22
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3DMark06 - 8655
160.02
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3DMark06 - 8652
So slightly slower than the official 158.22 drivers, but 3 points! I could probably run it again and get a different result. So I'm saying same score for me in 3DMark06. At least no major loss!
Games, well I tried Doom3, CoH and Lost Planet comparing them to the 158.22 drivers.
Doom3 (16xQ AA / 16x AF / Supersampling / Ultra) - 158.22 = 52.3 FPS
Doom3 (16xQ AA / 16x AF / Supersampling / Ultra) - 160.02 = 51.7 FPS
Wow.... 0.6 FPS lost. So, nothing to write home about there.
Lost Planet Demo ( 4x AA / 16x AF / Supersampling / High (bar Shadows - Med) - 158.22 = SNOW 35 FPS + CAVE 44 FPS
Lost Planet Demo ( 4x AA / 16x AF / Supersampling / High (bar Shadows - Med) - 160.02 = SNOW 36 FPS + CAVE 44 FPS
No improvement there either.

Although I have yet to play the game and test stability with these drivers. Nice to know no FPS was lost though.
Finally, Company Of Heroes. Here are the in-game settings,
CoH (4x AA / 16x AF / Supersampling) - 158.22
CoH (4x AA / 16x AF / Supersampling) - 160.02
As you can see, I gained 4 FPS for the maximum score. Average score remains the same.
To summarise then, it looks like for me no major FPS improvement or loss. They appear stable and I had no werid graphical glitches when running the benchmarks. One thing which will make me stay with them instead of changing back is the IQ. I know people always want to see an improvement, and most of the time it's just in your head. But to me, textures appeared slightly more clear and crisp with these compared to the 158.22 drivers.
So I'm going to stick with them for that reason. Otherwise the 158.22 drivers are just as good.
Cheers.