To me those tiny, expensive commercial units are not worth the trouble, and barely superior to cans.
This ^ in spades!
Sumps are great because they have so many functional advantages over canisters, advantages which have been detailed numerous times in numerous threads. But a significant percentage of the people who get a sump don't seem to do so because it works so well, but rather because it's a cool, shiny, high-tech-looking piece of plastic that they often display as though it is the main goal of their fish-keeping hobby. And many of those commercial sumps...when viewed through eyes that have used sumps for years or decades
as filters rather than
as showpieces...are utterly ridiculous and non-functional, with many design choices which are made entirely to look cool but which actually counteract the intended purpose of keeping water clean.
If you go to a home-improvement store and buy some fancy, expensive, designer flush toilet that costs a fortune...but doesn't really flush that well...and then you install it in a bathroom with a clear glass door that allows everyone to see your treasured new toy, and to
watch it being used...well, you're heading for that mind-set that leads to something like the Sumpmaster X-1000 Magnum Deluxe.