I've never used such a thing. If the intent is to get the LLM to not perform reasoning before it answers, most of the APIs have a toggle that lets you minimize or stop thinking.
I'd really like to understand why you'd use "Answer now" though; what's your use-case?
I never use it myself but was wondering does anyone ever use it. Apparently OpenAI, Anthropic leverage cerebras chips for something - i thought it would be for the "answer now" feature. Not sure though.