Just completed the 2 day M-school. While the one is still phenomenal the 2 day experience puts it over the edge on the second day! Much more track and skidpad driving. There is so much track time that at the end of the day, you really want to stop! I attended the school sponsored by the BMW CCA. This comes with the perks. I am not sure the same perks come with standard sign up. There might still be some room in the Jun or Jul school. Try to schedule a plant tour. It is worth it. Stonehands
I don't think there's any difference between the BMWCCA sponsored school and the regular school - the only difference is that you're surrounded by other CCA members. Having attended both the 1 and 2 day schools (I figure we were both in the March class together), I feel the same way as you that the second day helps you put all the pieces together and gain proficiency. I walked out of there feeling that I had confidence to get in and out of any situation with good car control. Well worth the money... now I just have to convince my wife that I need to attend the Advanced M School.