I've been using Kagi for the past 3 months, recently moved to the ultimate plan (assistant + search). I've highly enjoyed my experience, and I think the best analogy I can think of is switching from shopping for food at somewhere like Safeway or Walmart to a local organic grocery store. It's loads of tiny things plus a few large things that I end up seeing as benefits.
One of the things on the largest end for me that I don't see mentioned here very often, is how amazing the development team has been! It's tremendously refreshing and amazing to be using a product, encounter something not working right, write up a feedback post, and see it fixed in the next changelog. That's where the local bit of the analogy comes from. It's small, and I think that's brilliant. It makes you feel seen and heard, something that is absolutely beyond hopelessly lost when using any sort of Google product. You're a part of a paying customer base, you're not some minuscule cog in a massive conglomerate.
The pace of development is also wonderful. Getting new little features released often and watching the ongoing development with things like Kagi Map. I can only imagine this is what it was like to live during the golden age of construction and development in the US, seeing all these new buildings go up all around you.
There's also the search of course which so far has been great. I think it's power comes from the lack of ads of course but also the filtering, which makes it *your* search. Little features like appending @hn at the end of your search instead of site:news.ycombinator.com, or as mentioned by gutt3r_punk, the question mark to bring up the AI summary answer only on the queries that I want it to be on, not every single search on Google.
solid recommend