Thanks Lee for sharing this product with us, the video seems pretty convincing. I understand that there has been debate about viability of other similar products, such as 'cable safe plates'. Some were of poor quality, under a certain thickness for example. I see that this manufacturer states it's 1.5mm thick steel?
I guess when installing this particular product, you would be reliant on the manufactures specification and testing to some standard. I've search reg 522.6.204, and noted that # iv) can be difficult to achieve, not withstanding their demo video.
I note that the manufacturer does not suggest this product should be used concealed in walls, or have I misinterpreted your post?
Still not sure of the concept of concealing meter tails (6181y cable) in walls, and reliant on protection by this product. I note that it can be cut by a chop saw, guess someone with a wall chaser could do the same.