I have a photo trip out west (US) set up for next spring. (Gotta arrange these things well in advance sometimes.) I'll be taking the Pentax 645D rig with me, along with probably the E-M1, 12–40mm, 50–200mm & cool little 7.5mm Rokinon fisheye. At first my intent was to use the smaller system, with kit zooms, just for location scouting. But having used these two high-end zooms over the past few weeks I think this'll be a side-by-side deal instead. I might even leave my longest Pentax lens, along with the macro, at home. I can see throwing video into the mix too. Hello excess baggage fees!
-Dave-