Pros:
faster, more carrying capacity, WAY more range,
sit higher with your butt out of the water(especially nice in 45deg water), faster,
Customizing options are almost endless.

Cons:
Not as easy to transport, more wind resistant.

I carry 5 or 6 rods about 25 lbs of tackle a fishfinder, 14 gallon livewell, 12 volt battery, lunch & still have room for more.
I also find I get less fatigued in a pontoon boat on windy days.
I still have my old float tube but it doesn't get much use anymore.

Check out the Float Tube/Kickboat forum for lots more info. Almost everybody in BnT uses pontoon boats.
Mitch