Peter,

I have no personal experience with any of the models you listed,
but hope you realize that 1st generation are not known for
longevity. I don't remember just how short that life expectancy
is though. Personally, I have a Night Owl Optics model NODS3.
I don't use it a lot, but it is really a cool toy! At least in
the USA, it seems that all of these units are imported from
Russia. Not that this is a problem, I just don't know how many
manufacturers there actually are there, so I don't know if one
would be that much better than another or if it's mostly
marketing/packaging differences.

What is your application for the night vision? IF you intend to
use it a lot and especially in a high moisture environment, then
definitely consider one of the waterproof models you listed.
Mine isn't waterproof but I haven't really had the need for that
feature. I haven't done any night fishing in the boat (yet) but
would still take mine along if I did. I would just need to take
extra precautions not to get it wet. Even though mine is a lower
end unit, I'm very satisfied with the image quality. I also
appreciate the fact that it runs on 2 AA batteries. Since I have
so much stuff using AA's, I have a pile of Ni-Mh and they work
well with the unit.

Again, I don't have any personal experience with the models you
listed, but it seems to me that you need to mainly consider the
features of those models to make your decision based on your
usage.

-JimL