I'd appreciate thoughts or pointers on the following
1) Do people agree the integral 2 is appropriate or needed?
It is needed to avoid Gamma D which was jvc's failed attempt at hdr gamma. an HDFury device removes the hdr flag so the jvc doesn't go into the bad hdr mode. The integral may not be the ideal choice depending on what you want to do.
But note that if you strip the flag then you need a custom hdr curve and you have to manually select it each time you watch hdr content.
2) For example, would I have the integral strip HDR from the content (in addition to dealing with my 4k input on the JVC and 1080p input on the AVR)?
Well yes the device can strip to flag. Stepping up to the vertex will let you automate things Like switching the jvc to your custom gamma curve.
3) What's the opinion regarding sending HDR to the PJ vs. having the content converted from 2020 to 709?
I think sdr 709 looks great on our projectors.
4) If the integral converts the content, there's no need for custom (Manni01) curves, right?
Sorry wrong.
First it does not convert the content. It simply strips metadata, and can also tell the source device what to send.
Second to get decent hdr on our projectors you need a custom curve. You can download those that other people created but they seldom work great because the best settings are based on measuring the projector in your room with your screen.
5) I see the latest integral has macros automatically select the right curve based on the content, are people using that?
Yes the vertex can do that if you have created a custom curve for it to select on the jvc.
Some of this also depends on your sources. I use the Atv4k. The advantage is it can be tricked into doing tone mapping before sending our the hdr signal, though a custom curve is still required.
The ATV4k can't output 4k sdr 2020 but some blue ray players like some Panasonic's can I think, which is. Ice because you get wide color without a custom hdr curve.
All that being said Even though I have a custom hdr curve from a professional calibrator and I have full automation on the vertex for selecting the right mode on the jvc and I have the ability to get tone mapped dv out of my Atv4k, I still end up watching most content in sdr 709 because it allows me to have better black levels, lower lamp mode, and get longer usable life out of my lamp.