basically, more binds on the mouse could never hurt if you bind them right. Say in an FPS game, a lot of people have their guns bound to numbers. They can't move AND switch weapons very fluidly unless they scroll through them with the mouse wheel, which is still sorta slow. Bind them to the mouse, you can be moving, switching to the weapon you need, and never miss a beat. That's just something that I like. Not saying it's a necessity or that it will give you some competitive edge, just that it FEELS better to me. If that, as well as MMO binds, sounds good to you, then that's a good enough reason to pick one up.