Me and about a billion others would recommend JVC over Epson. But, I don't piss on Epson either. I think the 5040 has been a great projector for years, and their 4000 as well. It's very well reviewed and other than some serious power supply issues, the image itself has been outstanding. It's bright and vibrant with excellent colors.
But, yes, JVC has been doing things longer and if you can land a new JVC RS440, which was 'all new' for 2018, but barely better than the RS420, you should look into it as they may be had for about $2,500 right now from the right place. THAT is a pretty serious upgrade over some entry level models, and is really good as a solid first projector until native 4K is the norm.
I am wondering if the chips in the new Epsons are at all changed from the chips which have been used for the last few years. It does seem like there is all new HDMI processing in the mix, but from what I just read, it seems inconceivable that Epson has stuck with HDMI 1.4b bandwidth limitations. That is, it doesn't support 18Gbs HDR and HDMI, but the same limited 10.2Gbs HDMI that they have been using since the 5040 was released. Yeah, I can respect the solid image, but have to wonder if that information is even accurate. I actually hope I'm wrong on this and that they support HDR at the higher bit rates. Sorry you just bought your PS4 or XBox because you can't maximize the quality on your newly introduced 2018 projector. WHAT? Yeah, sorry about that.
JVC has been doing eShift and 4K for years now. This is basically Epson's second attempt. They really hit it big with the 5040, so this is very unlikely to be anything but a solid score as well. In a good theater though, I'm going to spend a bit more and advise as such if people can swing it.
Not sure, but I think JVC may have dropped all projectors anywhere near the $3,000 price point, so it may all be a ridiculous discussion once the RS440 models are gone. Yet, if Epson dropped the ball on full bandwidth HDMI, then DLP and LCD will be a tough call for the next few years.