Just recently I acquired a G1X Mark II. After initial trials I can state the following (rather subjective) findings:
- Camera reaction speed is quite decent for a compact. Of course it is not in the same league concerning speed to a decent DSLR, but for a compact it is pretty good.
- Camera useability with the new lens design is really good once I got used to the controls. There are lots of customization options. What is important for me is that both tapping the touch screen to set focus as well as manual focus work fine.
- Image quality may be the same as the previous model (I didn't buy the original G1X, so I can't compare), but it is not in any way comparable to a good DSLR. At ISO 3200, which is the default limit in sensitivity I can still take shots, which look good on a postcard size print, but it is not good for anything larger. Giving up on what I am used to in terms of image quality for me is the primary drawback in using it.
There remains the benefit of portability. Nevertheless, even if I can now catch moments I would have otherwise missed, I always rue the difference in image quality compared to my 5D Mark III or 1D-X.