That's exactly it, full frame or the em1 the pics I have seen from the em5 look amazing...EM1 looks the better camera, its also a little larger both in body and button wise which might be helpful.
I've been quite tempted to at least try one, I've been looking at moving back to full frame but looking over some shots I took with the EM5 a few months ago I half wonder if I should give the EM1 a try.