Hi this is my first post on here although I regularly visit the forum for Olympus help. I have the 40-150mm f3.5-4.5 and am thinking about selling up and buying the new 40-150mm f4-5.6 ED. The main reason being it's half the weight and smaller, although I don’t like the idea of swapping my old lens for a slower one despite it only being half a stop. I don’t use this lens that often but usually carry it around in my bag just in case I need something longer than my walk-about lens the 14-54mm f2.8-3.5 so the weight loss would really benefit me. Has anyone had both these lenses so some kind of comparison is possible? Any help appreciated, thanks.