When I go on one instance there doesn’t seem to be a change of interface or even a special about from the maintainer. Is there anything behind the scenes that changes?
The settings are often different. What is uses for autocomplete, what engines are included, privacy settings etc.
Some instances will query certain engines that others won’t. If you want google based results you probably don’t want an instance that doesn’t query google.
Geographical location of the server can determine your connection speed, the closer a searxng instance Is to you physically like in your home country the faster it will connect.
Some searxng instances are more popular than others, and the more popular an instance the more likely it will occasionally be rate limited. Choosing an instance that isn’t too popular helps even the load.
I like https://paulgo.io btw