I started going to the Yoga Institute (Houston location) about a year ago and rotate between this and two other Houston studios (The Hope Center and Joy Yoga) depending on my schedule and mood.
The Anusara yoga practiced here provides a nice balance of mind, body, and spirit. The space is beautiful and clean, and they have tons of yoga props that you can use during your practice. The teachers vary greatly in personality and teaching style - so try a few different classes to figure out which teaching styles and classes you prefer. Of the ones I've tried, I find I get the most out of the classes taught by Raye Lynn, Greg Smythe, and Janie Bowes.
-Portsmouth Street actually turns into a parking lot on that block. The studio is on the north side of the parking lot.
-You can bring your own mat, or just show up...they have everything there.
-The studio no longer has level requirements. When I started there, I was an intermediate yoga student and tried several different classes until I found the ones that worked best for me.
-At the beginning of each session (i.e., semester), they offer a free class week. They also handed free class cards for us to refer friends, so you could probably call and see if they'll let you try your 1st class for free.
The only con I can think of - it'd be helpful if they posted the detailed class calendar online so we could see which teachers and special events are are scheduled. Otherwise, this place is pretty much perfect. Go check it out!
Pros: clean, friendly environment, good equipment, lots of space
Cons: wish detailed instructor calendar was available online