I had Eheim model 1250 but I sold it and bought two maxy jets 1000 , I have them connected in serial, flow rate is now better beacuse of double max lift those pump provide, plus they are much smaller ,plus if one fail I still got one for backup, but those mag drive pump rarely fail, my computer runs 24/7 and I never had any problems. In restrictive system like water cooling in computer you need as much preasure from the pump to provide good flow. Eheim's 1250 drop in my system to 350l/h so you see preasure output (max lift) is essential, that why I started looking at little giant pumps, those seems to be very well build (Alu. casing) plus they put a lot of head. 3E family (200W yes not kidding) max lift 6.4m and still pumps 1200 l/h at 3.2m, so monster pump. A little more normal 2E family (100W) max lift is 3.5m, 550 l/h at 2m where Eheim 1250 deliver 0 l/h !!!! that its max lift. So I would look into those pumps Eheim is nothing special realy