Oh come on! This is up there with "those combustion engines will never catch on, the horse will always be with us!"
How can a fuel at sub 100% burn efficiency and a cost per kWhr of 6pish come out at the same costs as a air source? Gas at 4.5p fine but not oil.
If you want to see run costs try here http://bit.ly/1hSHVgi and click on the Eco Link Demo.
There is a hint of sense on the bi-valency comments but not quite a rescue.