E-p3 jpegs are different than e-m5
There are subtle but important differences.
I'd like to hear from experts as I am not one.
That said here is my assessment.
E-m5 has better skin tones, more realistic. Still a pink healthy glow, but more mature, the e-p3 sometimes made people too pink looking which personally I liked.
E-m5 defaults to darker pictures. That is in the default natural setting. Perhaps this is different in vivid. The e-p3 blew some highlights, but gave a bright look I liked.
E-m5 presents interesting settings needed for noise, there are some interesting options there.
E-m5 has much better ISO.