The guy at EMS was quite knowledgable on kayaks too. He mentioned that most people go with a hull design like the pungo for fishing applications but the risk of the large cockpit and hull design are swamping far from shore. It's not a design that allows re-entry like the sea kayaks do. The large opening is handy for fishermen getting in and out, but also allows water in.
He recommends buying additional inflatable bladders for fishermen who buy the pungo to add safety in the event of a swamping away from shore. This will reduce the water and raise the likelihood of being able to right the yak using an oar and some technique. Overall the keel and hull design is a good fit for fishing applications despite the added drag in the water over the trek style sea kayaks. The stability is worth the lessened speed though by far.
If the salesperson gives you any grief, have them call me on my cell phone to verify membership. I will answer my cell phone all day "Flyfishing Forum Member Verification" ;D