A friend of mine has a pontoon "boat" that he uses to flyfish from. I use a kayak. Both boats have advantages and disadvantages. You sit higher in the pontoon and it probably is somewhat more comfortable, but it is pretty useless against any real current. On the smaller rivers here in NW Arkansas the more manuverable kayak is definately the safer vessel. I can travel upstream against a pretty fast current (3 to 4 mph) for several miles by reading the river and keeping to the areas of slower current (backeddies and inside edges of the turns). I can fly fish effectively from the kayak but I usually get out and wade fish when I get to a good hole or run.