Actually, I have even stuck in 4 snowboards with bindings and 2 without totaling 6 boards. The FatCat 6 can hold 2 snowboards wide and 4 stacked. When the snowboards are on the aerodynamic advantage seems like it’s more negligible but I’d imagine that there is still a little advantage over other racks. It seems like it’s only more aerodynamic when there are no snowboards mounted.
The Yakima Fat Cat 6 has the best look and the best aerodynamic feel of any other rack I have come across.