I personally find it really useful, especially on those days when you're forced by circumstances to miss a shower or when it's really hot and sticky and you just feel grubby. I camp and I get going early in the morning, a palm-full rubbed under my arms in the morning does wonders for my morale. I often just rub it into my hair (although I don't have much these days) and use it to wash my face first thing in the morning as well, sets me up nicely until I stop properly to attend to my personal hygiene, which for me is usually, about 9 am.
It just comes out as foam on my hands, once rubbed in it just evaporates. Not sure of the cost, my daughter in law always buys me some before I go on a hike, I bet it's not cheap?
I like to take the small bottle rather than the large, it weighs less and takes up less space.