If I had only those 2 choices, I would take the HOB.
I don't believe the cans require less maintenance, I believe they require the same amount and frequency, and if they don't get it, become nitrate spewers.
Any pump with an impeller can be stopped or ruined by 1 grain of sand, or piece of debris, I've had it happen with cans (when I used them) HOBs, or any other.
Another reason any filter should be regularly cleaned, which includes brushing out the volute and impeller.
My problem with cans, is they make water look clear, and clean but the real issues (like high nitrate, and other invisible metabolism by products they produce) are easily overlooked.
A can came as part of the deal with my latest tank, but it sits dry, I doubt it will ever get used. I took it apart just to check it out, and the process, which would be the to clean, was a major pain.
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My choice is always a sump, although for an aquarist with only 1 or 2 average size tanks, a sump may be overkill.
For me hiding unsightly equipment like heaters, and other gear in sumps, instead of being visible in the main tank, the ease of maintaining equipment and filter media in an easy to reach sump, and the ability to add new water to the sump(as opposed to directly on the fish in the main tank) makes life easy.
I also find you can put sumps anywhere (they don't need to be directly below a tank), as long as the law of gravity is observed anywhere from behind a wall in a utility room (makes the sound problem go away, and maybe maintanence even easier), to even on another floor hiding all maintenance gear away, and helping to stabilize temps during heat spells, or near a floor drain where spills are less problematic, are all major plusses.
I have my latest one sitting off to the side in the garden, I can rinse gunk right on the plants.
Sorry for the tangent and derail, sometimes I just can't hep myself.
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