I think you have to decide for yourself what is most important.
Image Quality: BMPCC probably wins big time with the dynamic range and the raw editing options - But the GH3 is still very good Ease of use: GH3 - Flip-screen, oled viewfinder, lots of buttons, touch screen. Reasonable file sizes Lens flexibility: Both pretty flexible, GH3 wins because finding good wide angles or bright standard lenses for the BMPCC is going to be more difficult (and expensive) with the 3x cropfactor.
The GH3 is a much more complete camera than the BMPCC. The Pocket is just the cheapest way to get raw footage.
Jason Dimopoulos reacted to Julian in The full Panasonic GH3 review