Melting Point was the first studio I've ever done Hot Yoga at...and they have me addicted.
I attend the Wednesday Hot 26 Flow class, as well as the Saturday Hot Vinyasa class, and they are quite different experiences.
Hot 26 Flow is more of my kind of yoga. The instructor is helpful and perky (for a yoga instructor), and you get a pretty great workout.
Hot Vinyasa is a killer workout. I would not recommend doing a leg day prior to this session, however, as you will be doing lunges for 75% of the class. It's ROUGH. But man do you get your sweat on.
They are very understanding about letting you try a class out and then make a decision on the package you would like to choose.
Definitely try it out if you are interested. It's worth every drop of sweat!