is there a way to test if the the Disc is actually doing any good. I received one, although I was promised three. However the one I installed did not seem to make the signal any better in the room in question. This is a room over our garage which has a brick wall between it and the router.
The BT App will have a wi-fi feature for complete wi-fi customers, it lets you map the ideal location for the disc, then if there are still areas without good wi-fi, you contact BT and they can use that data to determine if another disc or two are required.