The fatter tires would be sweet in the sand. I have a few sand traps I have to negotiate when I ride near the river. Keeping the front wheel straight and hand on the throttle for full 750w bursts is the only way to plow through extremely dry and loose sand traps. The 4.8" tires at a low PSI would make life on the beach that much more fun.
I don't know if the extra width would also give you extra tire height and interfere with the bike frame with tight maneuvers at low PSI?