Netgear AC790S does not support the correct bands for 4G operation in Europe. It supports 700MHz but not 800MHz.

So far as I am aware, the fastest Netgear device supporting the bands used in the UK is AC785-100EUS, which is available for around £100. I have one, together with the DC113A Ethernet cradle, which I'm happy with. It doesn't have an SD card slot, however.