Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good stuff this

I have been using it for a while and it does what it purports as far as I can tell. It makes your hair grow fast I will say that--and with me it kind of changed the texture a bit, made it curl. It's kind of potent though, it can make your face break out a bit if you take two a day (The max suggested dose). One is plenty anyway says I. Oh and yes it does make your nails grow like the dickens.