Several locations, visit them all (they are dramatically different in ambiance, classes, and CROWDS) to decide which is best for you. Take the Yoga 101, and dip into as many different classes as you can. My boyfriend and I prefer the unlimited monthly passes where we've tried every class and almost every instructor. Most establishments do not offer such a variety so take advantage of it; personalize your learning experience. You will find some places, classes, and instructors you will not like but others will provide you with exactly what you're looking for. Whether it is to simply rejuvinate and receive a little oil massage from the teacher, or to work muscles that you didn't even know where there...Yoga Tree is a wonderful addiction to health and harmony.
Pros: unlimited pass & several locations leaves room to explore/learn
Cons: Hayes= usu. busy, Valencia=old building (dirty & can be hot)