I use it usually every other day and leave it on for 5 minutes. I find it really makes my scalp feel good. I haven't experienced any dryness or irritation from using it.
I've seen if for sale online. It was $20 plus shipping for 6oz. I got the body shop stuff $10 for 250ml, free shipping with 6. So that is why I did not get the T/Gel PO. Just google T/Gel Greasy. Takes a little searching, but it is there.