I have an XP3 and a 2026. I know the rating would seem like the XP3 should be more comparable to the 2028 but after its packed with media and slows a bit I beleive it is very close to the 26.
Some of my opinions are:
The Eheim is definately quiter, hands down. The XP3 though is quiet enough that its almost unnoticable. Most powerheads are noiser than my XP3 it seems.
Negatives - The Eheim seems to have trouble priming after cleaning the canister (see my other thread) but I am thinking this is because of the turbo twist capturing air. My XP3 has never lost prime since the day I installed it. I also think the mechaincal pad with the eheim is way to course, and the ceramic cylinders dont seem to do much. Pretty much everthing is caught by the final fine pad. I may have to try some custom filter pads. And the shape isnt ideal for cutting your own whereas the XP3 is perfectly square. I do like the filter pads in the XP3 but the medium pads seem to be a bit to fine and clog a bit quicker than I'd like. Also the green intake and spray bar kinda seemed like a joke... but mine came with additional intake and spraybar set, which were pretty good. Sometimes with the XP3 I worry that the disconnect lever operates to easily. For example when I am putting the filter back in place in the cabinent after a cleaning i worry the hose assembly might get caught behind it and the level pressed back so it starts dumping water, never happend yet but something I think about every time I do it. I should just come up with something I can hang the assembly on out of the way when manuevering the unit back in place.