I picked up the 900W (1.2HP) unit last week, connected the pump to (4) 250W panels in series (Slightly less power than recommended), and at peak day hours the pump ran in full power. I had it plumbed over the weekend, and all went well. This a well design product; however where what I see at least one improvements that can be made. Early mornings, and later afternoons, panels power diminishes but voltage is still above the 72V threshold; So the motor stays running at really slow speed and not moving any water. This could go on for an hour or two every day which worries me a bit. My plan is to order a photosensor relay board for few dollars and set the light intensity to a threshold: when not enough light is detected, the relay will signal the mppt controller to turn off the motor. N.C signal when enough sun, becomes N.O when not enough sun. Otherwise no complaints. This thing will pay for itself in 3 months if it holds. Definitely recommend.