The mouse has a neutral shape, but there are two buttons on the left side that you can hit with your thumb when using your right hand. Lefties can hit the buttons with their pinkies, but it’s slightly awkward. Over the course of a week or so using the G305, I found myself accidentally hitting the thumb buttons from time time time, specifically when I took my hand off the mouse to type, then went back to holding it. That phenomenon surely varies with the shape of your hand, but it seems safe to assume misclicks will happen from time to time. It’s not a deal breaker for me, but the shape of your hand could change that.