Very late to the game but finally got around to fitting a USB socket to my Superb. Got the part off a well known Chinese supplier for just over $8. It came with a loom that plugs into the existing front 12v lighter socket (at the rear of it) the existing loom then plugs into the new loom to maintain the 12v socket and a USB port just slots into one of the blank spaces. Works great and took minutes to fit by removing the side carpet panels.

Looks great, where did you buy it from?

Aliexpress.

https://a.aliexpress.com/_Eu95GwQ

Very easy to fit.

Thanks for the update.