Super flexible. I've never owned a wetsuit before but I've rented plenty of 4-3's. This one kept me so insulated. Fit's perfectly. The size chart was right for me. 6'-3", 195lbs, and I ordered a LT. Lastly, I've been so warm in this wetsuit. I always get a bit cold when surfing but I'm seriously so warm with this wetsuit. First time I used it, it was steaming when I took it off, it kept me so well insulated. I only give it four stars because this is my first wetsuit and I have only used it two times so far, but I'm stoked with this purchase so far.