I took a total of 3 classes at the ACSM in vegas last summer with Robert Sherman. I liked the class, but there wasn't any benefits you couldn't get without the $250 board. In fact, I took two classes on the same day and wasn't sore the next day -- I was disappointend. My boss had spoken to the instructor about purchasing the boards between the two classes, so on the second one, he was trying hard to give me a good hard workout, since I would be the one teaching classes at my gym, and I'm sure $$ were in his eyes, too. He was in my face the whole time, and like I said, I wasn't sore.
Long story made short, the boss decided against the investment and sent me to Pilates training instead. Pilates has truly improved my core and many others at our gym at a fraction of the cost to the gym owner.
And after I've had time to digest the situation, there wouldn't be many folks at my gym who would use them. We attract folks ages 35+ and they mostly live in the Jane-Fonda-where's-my-leg-warmers world.