Hello Helmich,
try this library: https://github.com/alexanderhiam/PyBBIO
I made good use of it on my Bone. I can’t tell you about the sample rate you can achieve with this one but the way it’s being used is maybe the most efficient way (of course you can get faster if you don’t use any operating systems and go for arm-code directly).
Cheers,
Bence
2012/11/1 Helmich <helmichdelange@gmail.com>