My brother recently got one and the screen is very noisy in live view, it's fine in menus. Also under low light indoors, lights are on, it selects iso 3200 at f3.5 sometimes f4 for 1/100 of a second. Where as my rx100 chooses iso 500 at 1/30 f1. 8. This is pointing at stationary objects so the rx100 seems to choose more sensible exposures and iso.
Apparently the rx100 sensor and lens combo is only slightly better so I didn't expect such a big difference.
Basically I am trying to find out if it's defective or it's just the way its firmware is set.