I saw a demo today of the Epson 5050/9400 and the JVC N5. Both projectors were shown uncalibrated, out-of-the-box. I didn't check the menu so have no idea of the settings in terms of brightness, contrast, etc. so these are just my raw impressions.
At home I have a 16:9 150 inch diagonal white 1.0 gain screen with an Epson TW-2000 UB projector that's 14 years old. The screen at Absolute Hifi was the same size, but may have been a higher gain as it looked a bit shiny at the centre. The player in the shop was a Cambridge 4k player. The room was completely light controlled and the wall were dark paint.
I brought Pirates of the Caribbean, The Fifth Element on blu-ray, Desk Set on DVD. I brought Sin City 2 and The Hobbit to try 3D, but they didn't have the glasses, emitter, etc. so can't comment on 3D, which is unfortunate since it is my main upgrade motivator. They also played a nature 4k demo called Les Sesienes.
My wife and I thought both projectors threw a nice picture, however neither of us thought the images were stunning, awesome, mind-blowing or any other adjectives that I expected I would be saying about these projectors. It was a definite step up from my projector, but incrementally. I expected the "whole other level" experience, but can't say I got it. For example, the black bars on both projectors didn't appear to be any darker than what I see on my old projector. Even the N5 wasn't very dark. markmon1 would have blanched white at this demo. Maybe the DI wasn't engaged.
We both felt the N5 was better than the Epson, but again, while noticeable it was more incremental than "whole other level". The JVC seemed brighter and skin tones more natural. However since neither were calibrated, even basically, I don't think it could in any way be considered a fair comparison of what they can do. I think there is consensus that JVC's are better out of the box than Epson. I noticed film grain or noise in both images, but the N5 was cleaner. I didn't hear any fan noise or DI noise, but also didn't try any scenes noted for creating them. I expected that both projectors would produce a much more film-like image, but honestly it just wasn't a big jump up from my old Epson.
We watched the Star Wars movie Solo when we got home. Even as bad as the contrast in that movie is reported to be (and it is in many scenes) I still think the viewing experience on my old Epson looked about like what i would imagine it would have looked on those two.
Sorry I can' offer a more technical appraisal. Others who have either seen demo's or purchased the new JVC's obviously have different opinions and experiences. I'n not denigrating the new lines, just wish I'd been blown away. Maybe that just shows how good the old Epsons are.
I will upgrade at some point, if only for the 3D and HDR.
My wife says I might as well get the JVC, but I'm at a quandary point. Since the image isn't mind blowing and this is first generation JVC 4k, do I hold off til 2nd or third gen before forking out 12 grand (or hopefully less by then)? Or go the riskier used JVC route? Do I get the Epson and use the extra money to upgrade my Pioneer 9.2 audio system to Atmos/DTS:X via Denon/Marantz/Yamaha 5.2.4? Can't answer these nagging questions yet, but at least I have a wife who says "It's more expensive, but I think you should go for the JVC. It had a nicer picture" and "get the Panasonic 9000 rather than the 820. You'll be happier." And I should mention, we are pooooor.