Yes, I used Henna Hut, and it was a very good starter henna. HOWEVER, it FADES. BIG TIME. I used the red, and within about 3 weeks, I would have to re-do it because it would be faded to a dull orange. I wanted the color to build up so I could reach saturation, and Henna Hut just would not build up. I don't think there is anything harmful in it, but there are things other than just henna. And those things don't stick. They wash away.
I switched to BAQ henna from Mehandi, and it is just as easy, an I am reaching saturation.
Bottom line, I don't think Henna Hut will harm your hair, but it will not stay that vibrant.