i don't even think Bikram is that good for a person(i've done it a few times at one of this guys studios her in NYC). When i found out Bikram was a former weight lifter i was like "ooh, now that makes sense"
its so gung ho and reckless in my opinion. there are more rigorous poses in other practices(vinyassa for one) and it seems to me that the intense heat is just magnifying what would be an average workout.

if you want intense heat, go to a sauna. if you want to buy into this assholes garbage practice, go do Bikram Yoga.

i don't need it and i'll argue that there are other practices which are consumately more challenging and beneficial.