Chatgpt vs Claude

I am just a beginner in writing, but recently, I have been having this Urge to write some life-changing book and am confused about which AI I should use. All along, I have been using ChatGPT for my study but don't understand this hype about Claude's sonnet. I have also tried NotionAi, and I can say it's good.

Now, question to other experienced writers out there: what AI are you using, and what are your reasons? And would also like to see your prompts such that I get guided on how to do this whole thing