When I ordered a batterygrip for my gh3 I was worried when I read a topic here about that grip having a mounting screw for the tripod plate that was totally off-centre making it difficult to balance on a steadicam. Since I wanted to use the gh3 with grip on my blackbird my first thought was 'not another accesory!' :))

But I just mounted the gh3 with grip on the blackbird and got it to balance just fine without an issue, the mounting plate that comes with the blackbird has enough holes to offset the camera to get it balanced, I used a 12-35 lumix lens on the camera. I thought it might be worth mentioning for anyone planning to buy the grip to be used on a steadicam, any other users here that had good luck balancing the camera/grip on other steadicams without having to resort to accesories to get it balanced?