I rarely use either one and have perfectly healthy teeth and gums. I believe in cleaning from the inside rather than the outside. A diet, like one rich in fruits and veggies, that rids the body of toxins and supplies nutrients to your gums and teeth so they can fight off disease all on their own.
"It is the business of a general to be quiet and thus ensure secrecy; upright and just, and thus maintain order." -- Sun Tzu, The Art of War
Mouth wash is much better in killing bacteria and more effective. Warm salt water is good when you have some bleeding and nice to have cleansing.