My pumps been working for maybe 80 hrs of operation over the course of a year of research. I am using the pump with PWM through an N-channel MOSFET on the ground with a fly-back diode and clamping zener diode. I also strapped a fan on the backside of the motor for cooling and even at 100% it's cool to the touch. When running below 80% is't not too noisy. The ground connections seem to be getting a little flaky lately or maybe it's my driving circuit.