I am a huge Alfred fan so can talk about that a bit.
Not familiar with Found, but from what I just read it looks like Spotlight file search plus the ability to search for your files stored in online services like Dropbox or OneDrive.
If you just want to search for documents, launch apps and that sort of thing, Alfred does not really add much to those basic tasks. Alfred even actually uses the Spotlight index for its searches. Alfred will allow you to perform a long list of actions on a file once you find it (see screenshot).
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The true power of Alfred comes from the
Powerpack paid addon you can read about at the link. Alfred also has a ton of user made Workflows
here that are very handy. For example here is a workflow that can access my saved bookmarks from the Pocket bookmark service.
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Take a look at
this older thread also.