I am after a small M4/3 camera with a flip up screen for candid photography. In the UK Certain stores are offering the E-PL5 and maybe other models with a free 17mm f/2.8 lens. I was wondering how is the focus speed of this lens on the E-PL5. Is it much quicker on this camera than on the earlier Pen cameras? I already have the P20mm lens and it's focusing speed on my GF1 is acceptable to me, it's a bit quicker on the newer G5. Also wondering the focusing speed and the banding issue on the E-PL5?