Having previously painted a section of our kitchen wall in the old house I still had nearly a whole can in the shed so it didn't cost me anything other than my time. Although the paint is supposed to be magnetic I found that it isn't particularly strong but for the purposes of my wall it didn't matter. I just wanted to create a wall that the girls could draw on with their chalks.
Because the paint is really thick and the magnetic bits sink to the bottom the paint needs a really good stir before starting. Using masking tape to ensure that I had a nice neat finish I covered the skirting boards, coving, door frames and all plug/light switches. Despite the paint being relatively quick drying I waited until the girls were in bed one evening before painting the wall. I just knew little fingers wouldn't be able to resist touching it.
The girls love it and there is always some sort of art work on the wall. It also works well as a family notice board and or a good place to keep a running shopping list. The best bit is that with a damp cloth it can all be wiped away for a fresh piece of art work.