The free school has one huge advantage. You can take the spousal unit. It was the first time I ever got her into an HPDE situation. It's clearly HPDE light, but she emerged with a huge smile on her face, and for the first time gained an insight into why I find track time addictive.
Also, when they "demonstrated the advantages" of DSC, I told them I just wanted to turn it off and have some fun, and my instructor said OK. It was wonderful skidpad session in someone else's 335i.
Never leave a car completely stock!