NV experience: nil
I came across a used pair of these:
https://www.agmglobalvision.com/agm-nvg-50-3al1
This would be for having fun and eventually a NV class. I won’t wear for work, and if the world ends, I’ll soon have five kids, so…we’re all dead anyway, no quick or quiet evacuation are happening.
Any opinions on pros/cons, experiences, better options for half off the new price?
AGM does OK with thermal, NV they aren’t exactly known as leaders in. They are known to use off spec glass and their PVS14s use that knockoff Israeli copy housing, not a proper Elbit or Carson housing. Most people that buy from them lament not actually getting a data sheet(s) for their units. Each NV tube is different and the data sheet is like a “pedigree” for a high dollar dog- it proves what the tube actually is or isn’t. In 2005 you might have considered buying NV without a data sheet, but no reason to not get one today. The other gripe is agm usually has a short warranty-1 year or so IIRC.
If the “used” set is anywhere near the $7200. price on the link, call me and I’ll get you a proper BNVD SG (not a knockoff) new with 10 year warranty. 
JRH is probably the only place I would purchase new, just due to your input on this site. The guy’s actually asking around $3900. It’s that “value” aspect that’s making me consider. Otherwise, I’ve expected to get a single tube setup.
Appreciate the kind words.
Price isn’t bad. See what he knows about the tubes- white or green phosphor, tube manufacturer and grade can tell a lot even if you don’t get a data sheet.
If you get any of this info and it makes no sense to you, post it up and I’ll try to help.