My thick, curly hair has been destroyed over the last year by--long story--a series of color and cut disasters, after the last of which the top layer of my hair simply stopped curling up and turned to an awful, straw-like texture. I've been trying everything to get it back to it's normal curly state, and finally turned to this Ojon mask, which I was told is particularly great for curls. I've now used it twice--which, for my post-shoulder-length hair, means I've used about two thirds of the pot--and I'm on the fence about it: The first time, I left it in for about five hours, and actually went running and to yoga with it in, so that heat was generated, and I saw a noticeable difference in my hair when I washed it out. The second time, I heated jt up with a blow dryer, wrapped a warm towel around it, and left it in for about an hour, and the difference was much less pronounced. My hair felt softer, but not dramatically so.
So, first, I'd say that this is a product that really needs to stay in your hair for a long time to work. If you can sleep with it in, that's ideal. But leaving it on for twenty minutes isn't going to allow it to penetrate the hair shaft.
But, second, I'm not sure, honestly, as other have said, that this works any better than coconut oil, which I've also been using and which functions in a similar way. If I leave it in for huge lengths of time, I really see a difference. Anything less, not so much.