The Bud's Diver is to trolling as pockets are to a shirt. I have been using these for three years and won't go to the lake without them. Whether one is trolling for Trout, Kokanee, Salmon, Walleye, etc., they obtain more hook-ups than flat-lining out the back of the boat and are much less expensive and easier to operate than down-riggers. I don't put a line in the water from the boat without either a Bud's Diver or Sidewinder Planer board in use.
Check out the videos on Bud's Diver here and the Sidewinder Planer Board by mousing over and clicking on the link for the Sidewinder.