I wouldn't say the bright corners are fear mongering to be fair mate.
I think its more akin to OLED grey scale 5% banding. Its there, and if you're a perfectionist - its extremely irritating but it seems to be a limitation of the technology.
It kinda is, the way it gets tossed around the forums. The fact is, it's a bi-product of the technology and it has a variance of fine to bad, which is factored into all manufactured displays. With content even the bad ones are missed by nearly every one until it's pointed out on full black, which is let's face it, practically 0% of a movie.
Fear mongering would (for me) allude to it affecting a small sample size or being essentially a made-up flaw. I think neither. Its there, its on every single N/NZ (with laser dimming disabled obviously) series sample I've seen [to varying degrees] and its clearly exposed with a simple test. Is it a big deal? Well thats all subjective. I don't think it is, and I think its way more palatable than OLED banding or LCD screen DSE or Epson's innate low contrast or Sony's contrast degradation BUT.. it is there. And its clear to see and it falls in line with the quantitative photos I'd asked for.
I think the overwhelming majority use laser dimming and therefore mitigating the problem, it's not made up - it's one of several bad flaws JVC have, like the contrast variance, and ropey HDMI, but again most people wouldn't be aware of it for 2 reasons. Content and their room - without at least a 2m wide black hole cove around your screen the image is compromised badly beyond these design flaws imo, especially with higher light output models.
Pretty easy to demonstrate too.
Extending this to someone buying a JVC projector, I'd absolutely respect someone who asked for a bright corner test OR asked for a contrast measurement at the CENTRE of the image and at the edges - this isn't fear mongering, this is just accepting the honest reality and limitation of the technology.
No retailer for the most part is going to pull a brand new unit out of the box, test it, give you the results and let you decide if you want it or not. They can however sell it to you, you can kick off about it and have said retailer send their measurements to JVC, at which point they might not even be remotely interested - in fact you'd have to get hold of the head of UK distribution to contest something like that generally speaking.
But then again, some people think 5% greyscale banding on an OLED isn't a big deal and they hardly see it. I just bought one from a user who swears he couldn't see it (and I believe him) but I can detect it on the content I personally use to run an OLED through its paces.
Is that content movies tho? I can make projectors over £100,000 show flaws up (and I'm sure I could do it with TV's as well) for example as mentioned, no JVC can delineate 4K properly, but again... content and context.
I was in a dealer's room, he was showing me a JVC and saying 'look, no bright spots' with a proud smile on his face (we'd spoken via email about it) - and I was really confused by his confidence given I could clearly see one on the top left.
Did you tell him? Don't forget that 'once seen can never be unseen' is very powerful. I can see laser speckle all day long and a few other things that I didn't even know the names of until a few months ago.
The very real truth is that JVC make really good projectors most of the time, nearly all of the time users don't see things discussed on forums and in the case of Sony they don't see the panel degrade either, until usually an upgrade down the line.
I was in a guys house with stacked projectors that had drifted, not subjectively badly either, it was like 3d without the glasses and when I asked when he was going to line them up again he said 'what?'
Suffice to say they're lined up now.