Our concerns are similar except we are on, and like to explore, loooong mountain lined inlets on Canada's BC coast where inflow (summer) and outflow (winter) winds can really whip things up with tall, steep, overfalling, short period waves.
Have not ordered this device yet, so cannot say whether it works as advertised, but it seems to be designed perfectly for controlling broaching in a following sea...and much more elegant than an old tire or bucket. Not a drouge, but a Seabrake; Seabrake
Me-thinks any vessel will broach if it starts to surf, because the rudder becomes useless when it's travelling the same speed as the wave. Surfing in a sea kayak is fun (to a point) but I sure wouldn't want to do it in a trawler