Think about how easy they would be to clean.....
Think about why you do NOT see many nurseries or container production using them because they are just not the industry standerd. Using high porosity grow medium and standerd pots is the ONLY way to ensure gas exchange. A pot with a few holes at the bottom is all you need with a mix that has high air porosity.
When I first seen one in the hydroshop I laughed .
They are easy to clean actually. Have you looked at their site?
I guess the Royal Botanic Gardens Kew and Edinburgh and the Forestry Commission's Bedgebury Pinetum as well as many others have just been fooled by good salesmanship since they use them.
It is a proven fact they are superior they are just not cost effective. Air pruning the roots leads to a larger root mass, something that standard pots cannot do. A standard pot can also cause a root bound condition, something that cannot happen with the air pot.
They can grow some species of trees in them that could never be grown in any other container before. Fact not opinion.
Edited by MotaMike, 19 May 2012 - 12:14 AM.