It looks like a pretty neat little unit. The only concern I would have is how low the resolution is. I believe it is around 80x60 pixels, so not a lot of detail. It will be great for detection, but you would indeed need to be quite close to have enough detail to ID I would think. For the price though, it would be a nice addition to a persons night vision kit.
Edit: clearly I didn't read well enough. I see you've put a deposit down. I would say any red dot sight would work reasonably well behind it.
I like your shotgun idea for vermin. I like that idea a lot. I think that is where something like this would shine, being up close and personal within shotgun range.