My favorite as far as ease of maintenance, that I've used, are 404s with the connector with a lever to cut off the water. I find them very easy to clean most of the time. As far as performance 403s are my favorite, but they're a pain in the ass to clean, I hate the hose connectors, but they seem to run forever without slowing down, unlike the 404s which seem VERY finicky. The worst filter I have is an Ehiem 2213(I think) It takes a week or so before it's down to a trickle and it's still perfectly clean!