They were asking for jet skis yesterday, because the motors were getting tangled on the debris in the water or were hitting the ground and the boats were to big to get into many places they needed to go.
All I could think of was my father cussing up a storm every time something got sucked into his jet ski, say a rope for instance, and the hours it took him, furious in the water, trying to get it out and unstuck.
Any boat you need to paddle would probably be the best in the mess of New Orleans streets. It might be slow but will take less time in the long run that you will need constantly fixing a motor or unclogging jet boat, not to mention the gas problem or the need of mechanics on hand.
The same risk of plugging is applicable to any marine engine, they all have to have a water intake to cool the motor, or they will seize up become useless.