I use Kagi search all the time. I often use the Quick Answer feature (append "?" at the end of the query, gives an AI overview/answer, then standard search results below). I never use the full Assistant - I have ChatGPT and Claude for chatbot use cases.
I like Quick Answer because of its ligtweight UX. Ctrl-T for a new tab in any browser window, type the question, get the answer. This is faster and mentally lighter than switching to a chatbot, typing the question there and answering. If I'm to use the chatbot, I don't see a special need to use Kagi's.
(my €0.02 as a paid user)
You can add some "bang search" (like your ? for quick answer) to use the other models Kagi supports like Kimi.
The quick model is there to be mainly quick.
This is generally how I use it too. Every now and then I click through to the assistant for follow-up questions. I appreciate that it’s there, even if I use it infrequently. The default kimi model gives surprisingly good answers too