I am wanting to do this as a little experiment. A recent fishing trip has me thinking that maybe my 'non-coated' downrigger balls might have something to do with my catch rates. I've thought this the last few seasons with no real proof. This year I was fishing with a family member with an identical boat, riggers, and rods and fished in the same waters, depths, speeds, lures, and distance from riggers. The only difference being the downrigger balls. Mine are round and lead and theirs were finned and coated. Their catch rates being much better than mine. I'm probably nuts but it gives me something to do in the off season.