Actually, Hydrogen only has 8% more lifting force than Helium: http://en.wikipedia.org/wiki/Lifting_gas#Hydrogen_and_helium

I ALMOST bought one. I tried to get four of them shipped to me, but after I entered all my information and submitted the form, it showed me someone else's shipping information. Makes me wonder if the site is designed to handle more than one order at a time. It is a pretty neat looking poster nonetheless.