I'm a bit biased, but I find the AI overviews to be basically great. All I want from a search engine is the correct answer, Google's knowledge graph has done that for many queries for a long time, and AI overviews seems like a good next step in that process.
I've not seen many hallucinations, fact checking is fairly straightforward with the onward links, and it's not like I can take any linked content at face value anyway, I'd still want to fact check when it makes sense even if it wasn't AI written.