ospy, basically eheims are just excellent quality.
I had a fluval 404 and it clogged SO quickly, it was unbelievable. After a week of filtering, the flow rate would drop right down and I'd have to replace the filter wool.
Eheim's pumps are very, very powerful. And by that I don't mean flow rate, I mean torque/power.
No matter how clogged the media gets, the flow rate never drops.
Yesterday I changed the filter wool after 2 months, a lot of filter wool too, big thick chunks of the stuff torn from a huge roll, and the filter wool was basically choc full of s-h-i-t. It was all dark brown, you could not see any wool.
Yet honestly, the flow rate never dropped. The eheims pumps are great.
Other canisters I've tried and internal filetrs can clog in a matter of days, but eheims never clog.
The fluval fx5 boasts a good flow rate, but by the sounds of it, the pump is not as powerful/torquey. Even ducati, the most ardent FX5 supporter here, admitted they clog and he needs to change the media fairly frequently.
That's the main reason I like eheims, they are solid work horses of filters, good quality and dependable. The fluval I had also leaked.
The 2260 is for my money the best eheim. I am not sure about the media capacity between the 2260 and the Pro 3, I think they are similar. But the 2260 has a slightly higher flow rate, and has the intake on the bottom, so no bypassing of media.