I took a ABCs one with The Asia Playboy. 3 days and 3 nights of intense pickup. It shifted my view of game from a tactical level to more of a beliefs level.
I have friends that have taken Sinn's BCs as well as Mehow's. Actully, one of my wings interns with Mehow.
But, If I were you, look at the companie's products (if they have them) and judge that based upon other companie's products. If their products is just a rehash of MM, dont bother.
If I were to take another BC, I would take an RSD BC. I attended the RSD Free Tour a few weeks back and think there teaching style is a LOT different then other companeis I've worked with. Also, they have TONS of videos of there teaching style.
Here are some free material from RSD to see if you like their natural style.
http://www.rsdnation.com/
http://www.rsdfreetour.com/
BUT! before you go to the BC, i recommend you actully sarge for a litte bit to handle your AA if you have it bad. There are BC guys who can't approach at all during there 3 days and waste all of there money... dont let that be you.