The effect of bleaching varies greatly from person to person. Some people respond optimally to teeth whitening and will get very white teeth, while others will only see a slight difference after treatment. People with highly discolored teeth tend to achieve more visible results than people with little discolored teeth.
From a person that hates flossing, this one is pretty good. I use it at max power, and its good at removing gunk between your teeth. My teeth feel cleaner af...