Bests & Worsts Reviews from Amazon

I just received these brush head replacements and I'm surprisingly disappointed. Based on the outer packaging, I assume these might be a Canadian version of the replacement heads I usually get. The text is in English and French. I've also found some notable differences in the brush models which can definitely be felt while brushing. Note: The left brush is the normal one I get and is about 2 weeks old. The right brush is this new one after only 2 uses. - Entire brush head is slightly more bulky, yet feels slightly lighter - Certain bristles in the upper portion are not as long as the typical model - Bristle material seemed different/more rough, not as soft. Slightly irritated my gums in some areas. These bristles are also lighter in color. - Bristle distribution is slightly different in some areas. - Mechanism doesn't seem to move as well as the typical model. It feels as though it vibrates but does not fully preform the "clean sweep action" that I'm used to. Overall I'm pretty sad that I'm stuck with these 3 replacement brush heads since they don't feel as pleasant or effective. I would have paid a little more for what I actually wanted. I'm glad that these work for some people, but I wanted to make sure others are aware of the differences.