I'm running seven eheim canisters right now. I've had fluval in the past but didn't like the ribbed hosing that is expensive to replace and gets filled with detritus. At least the eheim hosing can be swapped for clear hosing from the hardware store, and cleans easily with a brush. I also didn't like the suction cup primer on the fluval, and not too long after acquiring it the seal went on the pump head. I also found the inlet and outlet a bit tricky to place in the tank, it kept dislodging and hanging there. As for the eheims, priming can sometimes be tricky, and the parts are probably just as expensive, but eheim gets my vote overall. My oldest eheim has been plugged-in since 2008 and hasn't skipped a beat. All the original parts are intact, and it's running silently & smouthly.