Levels can be very useful especially when learning to shoot or getting used to a new bow set up. The level will aid in proper form and grip which is crucial for consistent accuracy. They are probably more beneficial on shorter axle to axle bows and bows with shorter brace heights which tend to be less forgiving on errors in proper form. I have used them before, but do not have one on my present hunting set up. I'm not a big tournament 3D shooter, so Ican't speak that aspect...I tend to shoot too low on those non flinching deer to score well.
