Right now I am looking to get a 70-200 f2.8 lens. Anyone out here have the Sigma? Is it compatible with the canon 40D? I cannot afford the canon lens at this time. I will be using this lens for hockey, drag racing and low light performances/concerts/night clubs acts and practically anything because I love photography so much. thanks for any input.

I don't want to make a purchase at this amount of money and be disappointed.

