I don't own a Bahiya, but I've demoed one several times and I've found I have no trouble edging the boat and carving turns....Back paddling to assist in turning as mentioned by the previous poster? I don't think so. YOU HAVE TO EDGE THE KAYAK! The boats initial stability is fairly solid, however, with some inexperienced paddlers, it may feel a little "playful." I can't comment on secondary stability due to the paddling conditions.
Rolling the boat was smooth and required very little driving of the knee to bring it upright.
I would probably consider owning this boat, but I wasn't as comfortable in the cockpit as other boats I've demoed and now own.
I don't mean to get into a debate about the Bahiya, but based on the info by the previous poster and the fact they're a beginner (in a more advanced design), and a rating of 5 out of 10, Come on!