I read a couple of reports and there seems to have been wind tunnels tests, presumably of a model or maybe full sized mock up I don't know. I had a look for the web site and it is a "work in not so much progress".
It just seems strange that something is at Farnborough that clearly is no where near being ready for the market. Is this normal ? It does look pretty good, although I'm not so sure the hype would translate into a usable machine.