I want a pancake lens for my new E-P5. I bought the kit, so it came with the Oly 17, f1.8. I want a slim lens for easy carry in certain situations. My questions are, 1) does the Oly focus any faster on the Oly body compared to the Pany on an Oly? 2) Are there any banding concerns with the cross brand combo? (I sold my Pany 20, f1.7 because of the banding, even at moderate ISOs, on my OM-D.) I'm hesitating on the 17 because I already have the bigger 17. I'm hesitating on the 14 because I'm afraid I might not want the wider angle and I don't want slower potential focussing. AARRRGGG!!! I'm so confused.