Those are the most basic of airbrush, no moving parts or anything. They have a tendency to sort of stipple the paint on, bit course. If you just want to lay a solid colour down it will probably do but if you go here
http://www.everythingairbrush.com/ac...tion_Feed.html
You can get a decent airbrush for £30 and do it all properly. Or maybe Jon RCS is selling them now ? I'm not 100% on that though.