I am going to rain upon your parade. There is NOTHING special about this lens other than the fact that it ranks highly in the 'pornographic photographia' annals. It is a sexy lens, just because it is so 'fast'. But, tallenpatterson, be not so fast with wanting a lens that is so, so, so soft wide open. You will pay anything from $1,000 to $3,000, money which could be far better spent with the Canon 1.2 (if you MUST have such speed.)
Not intending to thoroughly drench you with water, but a bit of cold H2O was necessary to force you to come to grips with reality. - David Lyga