The best variant I have ever had were Hobie branded "race blades" (what he's calling the white knight) and were a dramatic improvement over the predecessors. As he says the Lexan variant is easy to snap off particularly when they're old and the nylon variant is well, I guess you can call it a rudder.
https://www.youtube.com/watch?v=QoENzrViUIk
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Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
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