Quoted:
That was why I used the qualifier in my post that the buyer of used NVD's needed to do their homework. I spent about a year researching and learning about the NVD's I was interested in and looking for deals. I learned about OMNIBUS standards, what tube goes in what goggle, what the tube sheet specs meant etc. Some of it was valuable later on, others not so much. Ultimately, we are paying for the ability to see in the dark... If the NVD you are looking at (ALWAYS INSIST ON A 72 HOUR INSPECTION PERIOD!!) is worth what you paid the seller, then be happy and enjoy your new goggles. If you are a spec sheet weenie or measurebator, buying new would give you more satisfaction in your purchase.

I'll frame my comments by saying this: When I bought my first NVD, it was sold to me as a commercial ITT 5001, the civvy PVS7 that has a 51lpmm tube in it with a minor blem or two. I was really happy with the goggles even though they had a fairly early Desert Storm era tube in them (I pulled the housing off and looked at the date). These goggles did everything I needed and completely filled the function I bought them for. Then one day I was feeling kind of flush and had the opportunity to bid on a pair of pinnacle tube PVS7's on Feebay. The seller had no feedback, so I asked him to send me pictures of the front face and top of the goggle, and one with an object (pencil?) next to it to verify that he wasn't using someone else's pictures to scam me. Everything checked out, he was a shot show vendor who got in hot water with his wife for bringing them and a Raptor home and then didn't use them. When they got to me, the tube definitely was brighter and clearer than what I had but in my opinion wasn't better than the price difference I paid. Mind you, I paid $1400 for the 51lpmm PVS7's and $2000 for the 72lpmm pinnacle tube goggles-I didn't see on a practical level where there was $600 worth of difference let alone the HEEUUUGE difference between a brand new 51lpmm goggle from a dealer at $2450 and $4,000 for the pinnacle tube which was LEO only at the time, and probably still is.  I very nearly sent the new goggles back, but a friend offered a trade for a rifle he had that I wanted and we made the deal.

In my experience, you can only go so far wrong when buying NVDs if you do your homework, ask the right questions, and get an inspection period. If you do the following, most of the risk involved is accepable for a noob buying NVD's:

1)Ask for more pictures than the seller offers. Get a pic of the data plate to cross reference model numbers from the company website to see if it jives with the sellers description. Get a picture of the top and front of the housing to see if a .mil SN has been sanded off. There were a few PVS7's surped out by the USAF after DS1, so unless the seller has documentation for a serial number move on to someone else.

2) Ask LOTS of questions. Why is be selling? How much time does the tube have? How many and where are the blemishes on the tube? How old is the unit? Will you give a 72 hour inspection/refusal window upon sale?

3) Get a faxed copy of his driver's license. Use the info on it to research him. There are free websites that will confirm a name to an address, or a phone number to an address. The person you pay needs to be this person.

After all this has been satisfied, take delivery of the goggles. Is there a dark ring around the image? excessive (larger than small spots) blemishes that would indicate a dropped tube or a tube venting to the atmosphere? If not, and they work properly (ir light functions, switch feels positive etc) you are good to go. Play with them overnight and decide if you are happy. Chances are very, very good that if they came to you working that they will continue to do so for a long time.

Quoted:
While I agree with Dave to some degree (mostly because that is how I buy my own night vision). I also disagree. The main reason is most people don't have years of experience knowing what questions to ask or what to look for. They don't know how to remove and replace tubes to get information. They don't understand what all those numbers on a tube mean. The seller rarely has this info or provides pics of the tube itself. I have been in the NV game for many years , I buy and sell used stuff all the time. I know what to look for and what questions to ask but in the end it is still a gamble on my part with a lot of money. I am willing to risk the money and as part of the game from time to time I get burned. I think for MOST people buying new with a warranty is the safe way to go. The used game is full of land mines with tube swaps and unscrupulous sellers. I do not get burned very often anymore but I also have many years under my belt. In the beginning it happened a few times. Lot of money to gamble when someone is not as skilled as you or some others on this board.

No one on here is gonna care as much as the buyer when it comes to advice. We all try and help out the new guy but it is impossible to explain it all and give years of experience through a couple paragraphs. A prime example is the recent thread of a guy buying a ATN scope that turned out to be a Mini with a tube data sheet that was bogus. The data sheet was not even for a tube that would fit a Mini. God only knows what tube is actually in it. I sent him to Ed to have it cleaned,purged and find out what tube is in there (he did not feel comfortable taking scope apart himself). Used scopes can be a great deal. They come with big risks and you have to prepared to lose your money. It is an educated gamble for the experienced. A crap shoot for most. My .02 (The ironic part here is this is coming from a guy that sells a lot of used night vision. I still almost always recommend people but new with a warranty) I have never ever listed or offered to sell anything on this forum and others. I sell it on EBay. I sell honest stuff but I know MANY who sell junk. I have sold junk for parts and seen the scopes come back up for sale with specs and claims that are bullshit at best. Be very careful buying used !