These are an upgrade from my previous set of Harvard paddles. These are a dramatic improvement in control, spin, and sound (rather than the muted sound, the Butterfly paddles produce a traditional pong sound that helps identify the speed of the returner's shot. It also provides sonic feedback on the shot that you yourself have hit.) I can generate good speed, create predictable spin, produce touch shots, and direct the depth and angle of the shot. The price was great for 4 paddles.