I use PHD2 when guiding with my SS G3 CCD, but for fast cameras I think Metaguide is clearly superior, and is my preferred overall option (one of the factors in my choice of premium CMOS autoguider, over a CCD Lodestar etc.).
Details here:
http://www.astrogeeks.com/Bliss/MetaGuide/
It's a brilliant bit of software -- and also great for SCT calibration!