-- Last Updated: Sep-25-12 1:43 PM EST --
I have an older single-layer Avocet -- not sure of the year. The skirt that's worked for me is a Mountain Surf rubber-rand neoprene skirt.
I haven't been impressed with the performance of the bungee skirts I've tried on plastic boats in rough water.
edit: They were cheap bungee skirts with a fairly flat cut -- I suspect that a properly shaped bungee skirt would be better.