Maybe this will help.
Is the ND 5 not just the torch for scanning? And the ND 3 for mounting?
As all good stalkers we should use Bino's for scanning, Rifle scopes for aiming.
Isn't the 5 just a larger torch for added distance??
The nd3 looks good out to 250 so more than enough for night shooting.
I am going to try one of these out on my foxes over the next few months teamed with a cheaper end nv monocular.