Arm and Hammer do a baking soda one with enamel care - I always use some kind of whitening toothpaste and have not noticed any deteriation in whiteness with this one, I do remember when i started using the arm and hammer about 15 years ago noticing a fair difference in my teeth, obviously now that I use it all the time, I am not sure what they would be like without.
One of my sons has yellower teeth than the other, so I have let him use the enamel care one a couple of times a week and I haven't noticed that much difference yet, I am reluctant to let him use it every day until I have checked with the dentist that it is okay for children to use.