I finally tried Bikram. Not because I wanted to. Oh, hell no! I do "real yoga." OK, I do hatha yoga. In fact, I teach it. So I may be a little biased from the get go, though I know flexibility off the mat requires an open mind. In this case, I could use a lot of stretching.
I tried a heated hatha class in Phoenix, Arizona 11 years ago. Kind of ironic considering for six to seven months out of the year, if you did yoga outdoors during the day you could legitimately call it heated hatha. I wanted to try Bikram, but there wasn't a studio around back then.