I am not new to M4/3, used to own Olympus E-PL1 then sold it because needed a smaller camera for travelling. Bought Panasonic Lumix LX-7 then sold it because the low light performance is not that great. Nearly buy the Sony RX100 MKIII until I found a review for Panasonic GM1 by Blunty (http://www.youtube.com/watch?v=Hs3dkdtKimQ). From this one review I seek another review and another and another, finally I own it! The camera is tiny, smaller than the RX100.
From the review, GM1 kit lens 12-32mm OIS is damn sharp and it really is. This is the best kit zoom lens in mirrorless world even better than kit lens in DSLR world. The camera internal like the sensor, image quality and video quality are taken from Panasonic GX7 and that is great. The low light performance is excellent.
I also bought the legendary Panasonic pancake 20mm F1.7 (used) lens and it really brought out the best of GM1. Very sharp, great bokeh and really small and light. Great Lens for Street Photography.
Video also great and there is a video test by EOSHD Community that GM1 video quality surpass its big brother The Panasonic GH3 and Nikon D5200 DSLR (https://vimeo.com/80951606).
Many reviewers claimed the camera is hard to handle due to its small size. I really don’t have a problem with it and the touch screen really helpful. The battery life not so great, need to have a spare battery.