Both a Rotary Pump and a Vibration Pump do exactly the same job in providing approximately 9 bar of pressure to the group head (this pressure can often be adjusted). As a general rule, vibration pumps last longer than rotary pumps. Vibration pumps are usually considerably less expensive to replace. A rotary pump has two parts – the pump and the motor, and is physically larger. If noise level is important then Rotary pumps are less noisy than a vibration pump.