New Canon G10 and G15 Compare pictures.
You may also want to compare your G10 with the G15 image results here on DPR. Start with this page for Jpeg images with lower ISOs, then go to the next page with high ISO results, then finally to the RAW image tests. You will have to change the RX100 image choices in the lower right display results with those of the G10 by selection from the drop down choices window.
The G10 holds it's own at ISO 80, but loses ground as the ISO increases.