I tried this based on reviews elsewhere and it is definitely worth it. I have long, thick, fine hair. Since I started using this, my stylist only has to trim my ends about every third color visit. Amazing. I use quite a bit (again, I have long hair) and it soaks right in - no greasy feel, no weight - which is amazing for such thick stuff.
The only con I can see is that if you're into a lot of styling, especially a curl, it does not hold as strongly. But the tradeoff for really healthy hair is worth it for me.