I love the batiste dry shampoo, I have about 3-4 bottles of it as back ups so I never run out! The only downfall of this product is that I haven't been able to find the one for dark hair, so it's always a mission to make sure I get rid of all of the white powder! I tend to buy the smaller bottles, because I find that they're easier to travel with and take to the gym etc, without taking up heaps of space in my bag!
I use this when my hair is getting to the point of needing to be washed, but I really just don't have time to fully style my hair again (dry, straighten etc), and this product is a lifesaver. I find that you definitely need to spray a good distance from your head, or you will get white patches, then massage the product right into your roots. This ensures that you definitely get rid of the oil on the first go.
Sometimes I loose track of the last time I've washed my hair and thank god i keep one of these in my suitcase! Even though I'm brunette i just use the normal dry shampoo that comes out white, i hold it about 20cm away and lift my hair and spray under into my roots, then use my fingers to mix it all in. it instantly takes away the greasy shine and makes my hair look fresh for another day!
Tips: Dry shampoo is also great for creating volume in your hair even if its still clean