We always used them on rivers, they were the rig em right brand. The 3lb or whatever grapple anchors came with them were too light for rocky bottoms and current so we went to 5 gallon buckets of concrete to hold them steady. We had some issues where they would accumulate grass and weeds throughout the morning and get more weight and surface area and eventually pull anchors loose. Keep in mind this was basically a hard rock bottom trout stream with tons of current and wasn't very ducky, it was just close. We had great success on the backwaters of the Missouri river behind wing dykes with them. You really need to be organized with the main line and leaders because it makes an epic mess in a decoy bag otherwise.
I always felt their value was in calm, deeper water you could still have 30" decoy leaders and only 2 long drops to the anchors. I will use texas rigs over gang rigs whenever possible, including the 12 oz river weight versions instead of a gang rig.