SO easy to use - one coating and you're there.
make sure you use a brush without any metals on it (hake brushes).
the 1 liters are on their way back, as far as I know.
(unfortunately not the 5liters though)
any question on this, just ask.
(it is really easy to make your own emulsion also - if you stick to the simplest of recipies...)
good luck - it is highly addictive!