Here is an ISO group test amongst the NEX-5, NX10, GF-1, EP-L1, EP-2, G2 and GH1, done by the Serious Compacts.com:-
http://www.seriouscompacts.com/f41/mirrorless-camera-iso-signal-noise-shootout-nex5-nx10-e-p2-e-pl1-gf1-g2-gh1-314/
Well, I think the results coincide much with my own conclusions drawn from my own tests made (and published here) previously. In general, the bigger is better for the sensor but the Samsung is not much better here (but it is still slightly better btw).
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