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.
I cannot recommend this enough. I have an incredibly busy lifestyle and Batiste Dry Shampoo has saved my life on more than 1 occasion. It is so llight, easy to use and I keep several bottles as back up. Just remember to massage the product into the roots and check for white patches. I cannot say enough how much I love this product!