I have a Mag 9.5 return pump, and a Quiet One 3000 for my chiller. Both are in the sump, both get cleaned every 30 days.
My Mag 9 has been running 24/7 for 2 years. The Quiet One is 3 months old and will not re-start once powered off unless I hold it up to the surface and let it suck in some air, then it finally (slowly) starts & runs fine until it's powered off again.
The worse part (In my opinion) is I sent an email to the manuf. (info@pentairaquatics.com) 3 days ago now asking how to go about handling this as it's under warranty, and they have yet to respond. Terrible customer service.