It's super light. Lighter than an FF DSLR. A bit bigger than I expected, but still very small. The vertical grip is great, and unlike other cameras, and because the battery door is on the side of the camera, there are contacts right on the bottom of the camera, so you don't have to remove battery doors when adding the grip. You can quickly and easily just add or remove it whenever you want.
The lenses are large, but also impossibly light, too. I don't know what kind of sorcery this is. Even the zoom and the 120 macro were way lighter than I expected them to be.
Because of the above, it kind of feels like a toy, which was a bit of disappointment. Sans grip and with the 63 f/2.8, it'd be a good (albeit expensive) "walkaround camera" with an amazing sensor because of its size and light weight, provided you can deal with the slow, deliberate, method of MF shooting.
The Contrast-Detect Focusing is faster than I expected it to be, but it does hunt quite a bit, racking focus back and forth two or three times before it acquires focus – even in a relatively well-lit indoor space (like a camera shop). When it does lock on, using the smallest focusing area, focus is accurate and the results are sharp. The joystick is awesome to quickly navigate the 425 focus points.
Viewfinder blackout seemed incredibly long. It got a little annoying. VF does not blackout during continuous shooting.
Coming from using and owning a few Fujis, I was able to pick it up and manipulate everything without really having to wonder "how" to do something.
Both screens are awesome. The e-ink display for the top of the camera is awesome and easy to read. The tilt-screen is the same as the XT2, so it can tilt to the right as well, Kind of cool to be able to use it as a pseudo waist-level finder. Touch screen works well for selecting focus points, as well as swiping through and pinch/tap to zoom in.
I still don't really like EVFs. It's good on this camera, but not any noticeably better than my XPro2 or an XT2 (I still use the OVF on my Xpro, mostly). The EVF seemed to be laggy, but it was a "pre production" model.
It's comfortable-ish. I wish the grip was deeper to get a better grip on the camera.
It's well balanced – with the 63mm f/2.8 only. Put the 32-64 f/4 on it or the 120 f/4 macro, and it becomes fairly front-heavy. This is sort of alleviated a bit with the grip in place.
I didn't get to take any photos home on my own card, but going off of the rear screen during review, it's really clean through ISO1600, and 3200 is usable.
I was teetering (if I did buy one) between the 63 and the 32-64 zoom – The 63 is very sharp, and super light. I think the body (without grip), and a 63 would be the the best combo available at launch. I think the 45/63/110 would be the direction I'd go, if I decide to get one later on.
Overall, I was hoping it'd sell me completely on the GFX, but I'm not quite there yet. The 1/125 X-sync is still something that concerns me, as well as the (lack of) weight and my lukewarm feelings about about EVFs.