New NEX 7 has a name. What do you want in the 7m?

There are endless real-world examples comparing output of both sensors at high ISOs and showing that the NEX 7 outputs significantly more noise than the 5 or 6 series. They're not that hard to find. It is a widely accepted fact that the 5 and 6 perform better in low light than the 7.

The reason a larger sensor leads to better low-light performance is because it spreads the photo sites across a larger area. Thus the FF 24mp RX1 will have less noise than the 24mp NEX 7.

I'm not sure why the DXOmark scores are so close for the 6 and 7, but the score for the 5n is in fact higher.

It doesn't matter though. Charts and tests don't tell you everything, and in this situation there is ample evidence of the cameras being used in identical situations with identical settings and the 7 producing more noise.