with boards and divers you can get more lines in the water and still get them deep. I run 6 divers on my boat but I still run 2 downriggers when I have 4 people on board. I have 2 outriggers that I run with small dipsies on when I have 5 people on board. I can run 10 lines with this set up and cover a wider area of water than with just downriggers and flat lines. and I catch some of my biggest fish off my downriggers.