Brian,

I've seen similar products come and go many times.

They do what they claim, as far as imparting 'action' to the lures/flies tied behind them.

The real question is whether or not that 'action' is desirable.

Very few living things move like that in their normal habits. Things tend to glide or move gracefully through the water.

For the bass fisherman that uses spinning or casting gear, these would not be too popular. Soft plastics are supposed to be more subtle in their motions. If you want more action, there are crankbaits that will give you everyting from a wide slow side to side to a tight fast wiggle, with or without rattles from subtle to loud.

In any vent, if they are inexpensive and you want a more obvious 'wiggle' to your flies, try it and let us know how it goes?

Good Luck!

Buddy