NEX-5n w/sigma 30mm 2.8 vs. E-P3 w/panny 25mm 1.4

I know the two CSC formats have been compared numerous times by many different people, but I just want to gather thoughts on one specific scenario.

Which of these two set-ups would you pick to shoot largely static human subjects at night? Would the sensor advantage in the NEX be able to overcome the two-stop difference between lenses and the E-P3's IBIS? I know the focal lengths are different, but for my purposes, they're close enough.

Thanks!