The singular advantage I see of a non-invasive device (when they appear, whether the aforementioned one works or not) over an invasive device (and however you look at it, poking a hole in your arm is at least a little bit invasive) is the ability to take the device off to play sports.
I'd certainly want to see some actual test data, journal papers and some independent reviews before I thought about spending £1200+ on a device.
I do think this is in a different league to the £30 "Blood glucose" watches available on EBay, etc. (which do nothing except draw a pretty line with no sensor doing anything at all), but it remains to be seen what they come up with and how well it works.
I just thought it was of vague interest to see (perhaps) where they are thinking of pitching their price.