Are 40.41 detonators fully WinXP compatible?

Ok, so I installed the new 40.41 drivers and noticed that they weren't "digitally signed for windows XP". Every other official nVidia driver that I can remember WAS digitally signed; so I find this kinda odd. I know I downloaded the right drivers because during installation I can see "Windows 2000/XP drivers...yada yada" at the top of the screen.
I ran 3d Mark 2001 of course to test the drivers out, and my score actually LOWERED from 7400 to about 7100! Ooookay....these drivers suck. So then I'm playing Max Payne and all the sudden the game stops and I get a blue screen of death saying that the system needs to be shut down! This usually only happens when I've installed something that wasn't Windows XP compatible. Is anyone else having any Windows XP issues with the 40.41 drivers??
:confused:

They are beta drivers and non WHQL certified (Windows Hardware Quality Labs). This happens to any non-WHQL driver.