A RX100M2 (I have one) should theoretically be about as good as a APS-C/DX DSLR at ISO ~2000, thanks to BSI technology on their 1" sensor. I recently got a Nikon V1 as I think 1" sensors are already on par with older DSLRs in everything but depth of field control, which doesn't matter for the things I intend to do with the V1.