In every one of my current four vehicles, including the S2000, I have fire extinguishers and have had them in them (along with serious first aid kits) for years. Twice I have used them, not for me, but on other peoples car fires that I came upon.

I might add that this tall and thin extinguisher (Costco) just lies on the floor behind the driver seat and does not affect the movement of the seat (for me, all the way back) in any way. It does not slide around or make noise. Hanging bag is for paper maps.