One day is great, but if you can do the 2 day, it's even better.
Hell, I even sold the helmet they give away for $300 bucks if you need to defray some of the cost differential (I already had a helmet), and they include hotel and all meals.
08 E90 M3 Interlagos Blue
99 E36 M3 Cosmos, #2--Sold
99 E36 M3 Cosmos, #1--Sold