VPS will have a significant influence at an altitude if 10 meters or lower. I would recommend that you watch several YT Videos related to flying a phantom over "different types" of water and determine for yourself is the VPS can influence the stability of your flight. I routinely fly over the Ocean and Beaches. These flights are mostly at 75-150'. However, the few times I wanted to get video a little closer to the surface with VPS on, I had problems. @ a height of 10-15' over the incoming surf near the shoreline the Phantom was clearly influenced by the moving foamy water. If you plan to stay above 10 meters, then it's a moot point.