ive only used them while fly fishing and with very small size 18 to 26 flies. they work fine in big lazy rivers, but definately not in heavy pocket waters. if your thinking about using them on lures i think that the extra torque of the lure would pop it out of a fishes mouth when they jump. the only place i go to the barbless is the sanjaun, big lazy river, and the fish are also fat and lazy
I use needle nose pliers to flatten the barbs on my lures, works great, keeps the fish on better than barbless and makes releasing the fish a lot easier than with barbed hooks.