Seems a good price if its ok. trouble with boxes like this is support.
Haveing said that with dboxes getting more & more problems and more & more faulty ones from germany, might be tempted to try one.
Going to see if can get more info, images ect.
I know only emu software for sat providers for such a box. There is also a sat version on the market. Maybe its possible to patch that software for UK nagra provider.
The second alternative is to use a nagra CI-modul and cards.
The box offer 2 CI slots.