cost seems similar for fins.  thruster boxes look stronger, but if you were to break one you might break your boat instead.  4wfs looks weaker but should break away without hurting boxes.  I  got caught in a surge and landed badly out of control, almost dry, 5 mph belly flop on a steep sand and cobble beach and didn't break 4wfs fins.  I had thought for sure I would take damage, but nope.  I'm 200lbs also.