I've been using this for years - it works!
First of all, you can't expect the same results with this product as you can with a salon treatment.  I have wavy hair that "grows" when its humid, but this stuff calms it down for about 6 weeks. It doesn't completely straighten my hair but that's okay with me.  It doesn't smell the greatest but its only noticeable when my hair is wet.  I like that I can wash my hair immediately afterwards and that it doesn't cost $350, which is my salon's price.  Make sure to use sodium chloride free and sulfate free shampoos.  That's important.
Rating: 5 stars