Diff. Between Single & Double Concave

hi all. was checking out the specs on the new boards. namely LF's Watson and PS3. Noticed that they have a different hull shape to aid riders on softer landings. The PS3 uses a single concave, while the watson is one a double. What do you think will be the difference? Anyone got any input or first hand feel of the difference? thanks...

uhhh one concave.

A concave is a bottom feature that directs water and can speed up or slow down a board. A single concave directs water the outside edges of the board and a double funnels water more towards the center.