EM-5: boost in-camera ISO v post processing

Is there any advantage to increasing the ISO in camera over leaving the ISO set at 200 and changing settings in Lightroom (or the like) if one is shooting RAW, assuming an equal amount of light falling on the sensor?

In other words, increasing ISO causes the camera to increase the amplification of the signal and increasing the exposure, etc. sliders in LR also effectively amplifies the signal.  Does the E-M5 do a better job or does LR?

I'm ignoring issues such as metering or being able to see the image on the camera monitor (or OOC jpegs) and concentrating on the appearance of the final  processed image

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