The similarities among the three sensors used on each of our three models should normally result in a very close behavior as well.
But starting with the Overall score, differences arise. The G12 is clearly ahead with 47 points, while Samsung and Nikon score respectively 40 and 39 points. Two use cases are in favor of the G12: portrait, with a 20.4-bit color depth (more than 1 bit better than the other two), and low-light ISO, for which the G12 reaches 161 ISO, about 1/3 stop better than the Samsung EX1, with 129 ISO.
When we analyze the metrics, the close performance behavior of all the competitors is obvious, with SNR, dynamic range and tonal range being very close from one model to another.
In summary, the three cameras show very similar behavior, although the G12 has some slight advantage for very low ISO and a greater advantage for color sensitivity.