Is the answer Will Buckley?
Never really thought about it as I don't think the words are that similar and therefore not interchangeable. Fast refers to speed, and quick refers to time
For example, I would never say "You are driving to quick" or "We need to have a fast chat"
Quick or Fast ? Which word do you use? I almost always use "quick" as I'm from Sussex (southern England). Fast is for northerners.
Test: who is the quickest/fastest/most rapid/swiftest winger?