I highly recommend the Rena. To get it primed, they give you a funnel and you pour water down the intake tube; you don't have to suck it up (although I've sucked my fair share of aquarium tubing (think crappy non-self-starting siphons!)) Better than the easy priming, unless you empty the canister filter and dismantle it, you never have to reprime. It has a quick-disconnect hose setup, so you unplug the filter, and flip a little latch and clean out your media, and put the connection back in and it's already primed! I also like that the intake can be put on the opposite side of the tank as the output, so you have better filtration, as the water goes in one side and out the other. It also comes with a spraybar attachment (a little short, but works well), and clear hoses, so you can hide them down the corners of the tank. And the hoses are all you see since it's an external canister filter. The only downside is that the filter itself has to be kept below the tank, although this isn't a problem if yours is on a stand. And the media area is pretty small, but I've modified the setup in mine and put the biological media under the media basket. Otherwise I think it's the best filter I've ever owned.
