I bought one about about a year ago and wondered the same thing. I’ve used ebay for lots of stuff but used items were going for similar prices to new and the cheaper ones were clearly fakes. Now many people find the fakes to be quite ok but I spent the (huge sum of) money on a genuine one from Flightsimwebshop. At the time they were the only ones who had it in stock.
The TrackIR5 itself is excellent, it takes a bit of setup so that you can look around completely yet not be too jerky but is totally worth it. Even if you’re just single player doing circuits in one of the free aircraft you’ll see a real benefit. I have found the TrackIR to be reliable, easy to use and I consider it an essential controller.
It is very expensive for what it is and I kind of resent having to pay so much for so little, but I was not convinced by the reviews of similar but cheaper products. I intend to keep flying and I expect to get many years of use from it. Finally there is the re-sale value. You can sell your used item and not lose too much money in the end.
I hope this helps.
