Extremely hard bristles and no available replacement heads
This is so hard that it will definitely tear up your gums and maybe damage the enamel on your teeth.  I tried to find some soft replacement heads on Amazon and what do you know -- there are none.  Unlike most of the other "Oral-B" type toothbrushes, these heads have a different size connector to the handle so there are no replacement heads.
Rating: 1 stars