Exactly. As an aquarium hobbyist there is a massive price difference between pumps. Something with the same specs on paper can cost €50 for a cheap brand vs €250 voor a top brand. But the top brand sells parts online and has manuals listing all the parts and serial numbers . They are also available after 20 years and run more quiet and reliable overall. The cheap or nameless pumps are made to throw away when they malfunction, which they do in a few years.

The nasty part is that there are brands which charge top dollar and pretend to be top but sell you crap anyway