Not the best!
This brush does fairly straighten my hair, however the little red tips at the end of the bristle always snag my hair even after I have combed it before using this brush.  Also, if you have frizzy hair, this brush doesnt really tame it down as much.  It can take longer than a regular flat iron to straighten hair with this brush, so it really didnt get much points on time saving either.  Overall, I am not keen on it and will be returning to find another brush that actually works better.
Rating: 2 stars