It only cost 65 cents! Baking soda is all natural and helps whiten your teeth, but I will say that I'm not a dentist and I wouldn't recommend using it for every brushing. Instead see how it goes by using it for either your after lunch brushing or one other brushing, whether it be morning or night.
It is slightly abrasive, so it's good to use either a fluoride rinse and/or toothpaste the rest of the time to help keep your enamel from being worn away. I'm not going to argue with you over the good or bad health risk of fluoride, that's not what this forum is about. Here's a link that discusses the pros and cons.