Purchase Decision: OM-D EM-5 or K5II

They are both awesome cameras.  But what is going to be used more when you're on the go?  I chose the 4/3 because I take it everywhere .  I originally bought a PEN-e-PL1 .  I bought/tried/returned a canon rebel, panasonic dmc200, a sony A57, and a sony Nex6.  I kept the PL1 because I could not find any difference in quality on blown up and cropped pictures.  I was floored by the size of the canon and sony dslr's and really didn't want to lug them around.

I was so impressed with the PL1 that I bought the OMD-F EM5.  I upgraded the lens to an 14-150mm  lens.

Since they all take awesome pics, for me it boiled down to quality, ease of use, carry size, and easy use of menu.

Hope this helps