My problem with the GH5 is that the improvements are not worth the cost over the GH4. The main draw is of course the 4:2:2 10-bit internal, but that has some issues. There is already websites finding some issues with the internal recording, not to mention the fact that its currently maxed at 150mbps recording. Yeah, 400mbps all-i has been announced, but who knows how good it will be - if it ever comes, and its still going to be in a crappy AVC/MP4 format.
A better option is my opinion is still a GH4 with an Atomos Ninja Flame. For around $2,200 total (cost of a new GH4 + Atomos), you get a camera capable of 10-bit 4:2:2 at ProRes and DNx post-ready quality, the ability to monitor v-log with a lut, high res 7" 10-bit HDR screen, and all the scopes and meters we need to be happy. Slap a $160 Tascam DR-60 on there, and you have a full-fledged production-ready 4k camera. With the GH5, for $2,000 - you get a GH4 with minor upgrades - no external screen, same crappy AVCHD/MP4 recording, limited scopes and graphs, tiny tiny screen, crappy audio solution relying on internal audio recording...
Basically, I see no advantage to a GH5 to someone looking to get a GH5 without currently owning a GH4 (about the same cost for a GH4/Atomos), and I certainly wouldn't recommend an upgrade from the GH4 to the GH5 - I'd say get an Atomos and have a better production camera setup.
I own a GH4 w/ vlog, Atomos Ninja Flame, and Tascam DR-60 Mark II, and I can tell you - the quality of the image off the recording at DNxHD 220x is stunning, as is the audio quality. I fail to see what a GH5 would offer to me.
My sole reason for getting the GH5 is UHD 60P. Nothing else. It will be an improvement over my Sony FDR-AX1. Always used on a tripod, fixed and have ordered the XLR unit for audio. Will not use Vlog and if I need 10bit will get an Atomos Inferno. Everyone has different reasons for getting cameras for particular features that meet their needs. As you will see to get UHD60P the other camera options are really expensive. By the time one gets batteries etc the GH5 is likely 5 times less costly as the closest competitor, FS7 with the cheapest set of accessories. A wonderful camera but not in my price range.

