Product review (5 stars): Good for volume, smoothness and loose curl
This thing works pretty good, it's just a little tricky if you use the rotating feature you have to make sure you're going the right way.  It does add volume like a large round brush and blow dryer.  The benefits are it's easier than winding hair around a brush, then picking up the blow dryer and putting it down every time you grab a different section of hair.  It also leaves my hair smoother than brush/dryer.  Definitely less frizz.  I would recommend this.  I did not use the round comb like attachment, my hair is too fine to get smoothed out with this.  The brush could be a little stiffer and that would work better picking up a section of hair but it does work.