> Is quid really used in UK by 80-90% people?

I deal with Brits on a daily basis.

I seldom hear them use the term "pound". Everyone says quid.

Pretty much everyone uses it in informal settings in my experience.

In a professional environment, people usually say pound.

The distinction is context-based, not class- or education-based.

It's my understanding the same is the case for kuai vs yuan as well?