I have the Colorado Bag Co, big bag. I think it is 10gal, & I used it successfully on a Nacra 5.0, N5.7, & H18.
When testing it, I flipped the N5.7(19') on a nearly calm day. It took the entire bag full, I only weigh 170lb.
If there is any wind you need less water, & once the wind is appx 20mph, I can right it just by hiking, the wind on the tramp works in your favour.
I would suggest a 3:1 purchase, with cleat, to attach the bag to the righting line. It is very difficult to hoist a full bag up, then hold it as you hike.
With a purchase you can easily hoist the bag exactly where you need it, then simply step inside the line & hike out.
I use this-
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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