When we got our hp a few years back there was a hp guy in the shop to promote them and he said that it used air to clean the heads and not ink? But I wonder how true that was! I don't use it that much and just get annoyed with the out of date message Back to the TV program it was comparing it to what you get for the money which open your eyes when they said "40 or so bottles of fine whisky, 40 or so bottles of fine champagne and X amount barrels of crude oil" makes you think that its a massive rip off. I wonder with some internet research where and what would be the best ink you could buy to do it yourself, as I don't think those printer companies mix there own but buy from some specialist supplier?