Lablab beans - Has anyone grown (or even heard of) this?

I was just flicking through the fruit and veg section of the RHS website, and I came across this:

http://www.rhs.org.uk/Gardening/Grow-Your-Own/Veg-A-to-Z/Lablab-beans

From the little I've just read about them, they seem like the perfect veg for the back garden. It looks like an ornamental, but its food. Win win situation.

 

Not heard of that before, would be another one for the edible herbaceous border.

 

I grew these several years ago after RHS Wisley had a few specimens in the Penelope Hobhouse garden. Ruby Moon was the variety. I wasn't aware at the time that they were edilble so I just grew them as an annual potted climber.... they're worth growing for that alone.
The beans are half moon shaped and deep purple in colour.