I bought a GX7 and later sold my trusty old G1 and added a G7 to my little collection and along the way picked up the excellent 12-35mm f2.8, and Olympus 9-18mm and the tiny and shockingly good 14-42mm Mega OIS. I couldn't get on with the grip on the G7 as it annoyed me every time I pickled it up so it went.
The 12-35mm f2.8 was a revelation to me as for the first time I had a MFT zoom that gave me a FF look... allow me to explain... with previous MFT zooms I had an aperture range of f3.5-5.6 but with the 12-35mm I could have f2.8 throughout the range which gave me pretty much the same look I'd get from FF at about f5-11 or so which with FF would be about where I took most of my pictures. The way the dof falls away gives a FF look at f2.8-4 or 5 or so that was difficult to get from the f3.5-5.6 zooms.
G7 and 12-35mm f2.8 at 33mm, f2.8, 1/1,600 and ISO 200. Mrs WW...
This was taken with the same lens on my GX7...
GX7 and 12-35mm f2.8 at 35mm, f2.8, 1/400 and ISO 400.
I sold the GX7 and bought a GX80 and later added a GX9.
To be honest I can see no real difference in image quality between the G7, GX7, GX80 and GX9 but the GX9 has the advantage of being 20mp instead of 16mp.
Just a few more pictures
GX80 and 45-150mm at 150mm, f5.6, 1/500 and ISO 16,000. Yup ISO 16,000
It wont be great printed 1m wide and viewed with a magnifying glass but as a whole picture it looks fine on screen and will be ok as quite a large print too.
A couple of GX9 pictures with the teeny tiny 14-42mm...
42mm, f5.6, 1/500 and ISO 200.
24mm, at f8 for deep dof, 1/800 and ISO 200. Mrs WW again...
Where I am now...
I now have the GX80 and GX9 and I'd use either at any ISO up to and including the max of 25,600. My lens line up is now Panasonic 14-42mm Mega OIS, Olympus 9-18mm, Panasonic 45-150mm, Panasonic 12-35mm f2.8 and Olympus 17, 25 and 45mm f1.8's. I think that'll do but I may add a long zoom at some point