I received a free olympus battery grip when I bought my EM1. I haven't used it at all but have kept it since it was bonus. My largest lens is the 12-40 which I feel is fine on my EM1 without battery grip. At this point I don't shoot a lot of long telephoto, I don't see this changing but you never know. Any reasons for me not to sell the battery grip? Not sure what the going rate is for a battery grip these days, maybe it's not worth the effort of selling?