White is definitely better for seeing weeds. My boat currently has one white and one black rudder (long story, and I'm working on it).

Anyway, at Madcatter, there were lots of weeds this weekend. They were pretty much invisible on the black rudder, but were very easy to see on the white rudder (even though it was extremely dirty/stained). Even with these old plastic rudders, the boat was pretty fast (led both races all the way to the gate, then the wind shut off and I made some strategic errors).

I have a set of white racing rudders from my last Hobie 16 (not sure of the exact age of these rudders, probably around 2006 or so, and barely used). I'm getting them redrilled for the Wave. Probably overkill, but I like these rudders (just can't let them hit anything solid, or they will chip pretty easily), and I can't see buying EPOs while I still have these available to use.

Mike