Hello - I usually just read and don't participate, but had to put in my two cents on this topic!
I used to be on the fence, going between drugstore and salon quality. I'd use Pantene, mainly. Found Aveda to be very drying on my hair and irritating to my skin. Then I tried Kerastase and that was good, although not enough to sway me ($$$). About a year ago, I started using Davines OI shampoo and conditioner, along with the OI milk and beauty potion before blowdrying.
Holy cow.
I will never go back. Softness, volume, amazing smell, nourishment ... it's a fabulous product for all hair types. I have fine hair, but lots of it. The OI line is AMAZING.
If I use drugstore shampoo and conditioner now, my hair feels like straw and is limp and difficult to style. With the Davines, I can rough blow dry and it falls in waves (okay, my cut has something to do with that, too). Seriously good stuff.
http://us.davines.com/search/products?q=oi