I went to Lori's Hot Power Vinyasa Flow class with my grandpa. Easily, this was one of the best yoga classes I have ever taken, and I have tried many between San Francisco and New York. Lori's positive energy is infectious and positively genuine. The class itself is an awesome workout, but somehow she makes it not seem so intimidating.
The Hott Spot studio itself is a very welcoming space, which seems to reflect the sense of open community among those who come to class. The studio space is medium-sized, so could get crowded, but didn't feel crowded with about twenty-some people in class.
TL;DR : Phenomenal studio with top notch instruction. Wish it were near my home in Brooklyn, but I will definitely return next time I'm in the Pittsburgh area.