This is why dynamic range of new Sony sensor is needed

And Panasonic G5, G6 and old GH2 may not be good enough.
Here is an example of photo taken with E-PL5 under bright sunlight. Dynamic photo, so no HDR possible. The photo is exposed OK for given changing conditions. Feather head-dress and legs at top-left are overexposed already in RAW file (checked with RAWDigger), so I could not expose shot more.

The light was so that for the best look -100 highlights/whites, +100 shadows and +1.5 EV exposure were required in Lightroom. Try it with your old camera and see what happens.

LR settings

OOC JPEG, minimal contrast (-2)

Final photo

Any camera with less DR than E-M5, E-PL5, E-PM2, or that largish GH3 would cause problems to deal with - more noise. I already had to use 3rd party noise reduction software (Noiseware Pro) to get rid of the noise with E-PL5 because Lightroom can't effectively deal with it, you can see results on the photo above. IMO the result is good but any more noise than that would be pushing it - would reduce resolution.

GH2/G5-6 sensor will produce 0.7-1.0 EV more noise, and I it will reduce resolution after NR, plus it will give more headache to deal with.

This isn't applicable to you if you avoid photographing under bright sunlight without fill flash or another light control. But, for someone living in always sunny California, and shooting everything in every condition the DR important.

I came to posting this after processing photos from San Francisco Carnaval, bright sun, I couldn't control position/subject, but I still wanted to take good pictures. This thread: http://www.dpreview.com/forums/post/51574570