I got a groupon for a float session and used it last month at a place in Abilene, Iam. It was an amazing experience. Very relaxing. It took me about 15 minutes to get used to the feeling of weightlessness and just relax, but the rest of the session was fantastic.
I'm a big guy (6'3") and it was big enough for me to float without feeling claustrophobic, putting my arms all the way out and even behind my head. Cost was decent, too... about the same as a massage w/o extras
I went to the Refresh Spa near Primetime and Copper Creek, but I heard there is another place in town.
It isn't true sensory deprivation as even when you close the lid to the pod, the seam still lets in light from the room and there are lights on the inside if you want to leave them on. Don't be surprised if you fall asleep for a bit though.
Have fun.