What are the best yoga studios in San Francisco for advanced students?

I've practiced Ashtanga, Tripsichore (hot room) and Power Vinyasa Level 3 (hot room). I am working on inversions and I cant seem to find an equally challenging class by doing a google search. Ideally Level 3, preferably hot, but not Bikram. Please help.

http://www.quora.com/Yoga-in-San-Francisco/What-are-the-best-yoga-studios-in-San-Francisco-for-advanced-students