Akashi
Regular
There are lots of pages on the web where you can compare all sorts of test shots from both camps side by side.
I had an EM-5 with some lenses for a little while and sold it because what I got out of that camera wasn't up to my expectations IQ wise (for that one camera solution I aimed for back then) and I already had a NEX-7 and some killer Zeiss glass at that time (still have it). The only thing I miss from the Oly is the fast AF and the compactness but you can't have it all.
For my two APS-C cameras (NEX-7 and X-Pro1) I have enough lenses that deliver all the sharpness/resolution I could ask for ... and more.
Yeah I know. I do find this a very tough choice. Mostly because the cameras (both Xt-1 and EM-1) are so darn expensive. I have the camera in hand now, will play with it over the weekend before I have to make a choice. Thanks everyone for chiming in!!