Prop swinger - I was describing the existing situation in the US, where most GA worldwide occurs and where the mention of Q-anything would gather only a blank stare, or perhaps a gentle smile of recognition in recalling Q-codes as a long obsolete and slightly bizarre concept from the history books, right next to Morse code as primary communication. QNH is called by that name today (in some places) only as a necessity created by those, mainly in the UK, who refuse to let go of the Edwardian past, including its arcane and today pointless navigation practices.
Given widely available altimeter data, it is normal worldwide practice for all low altitude GA aircraft to use a common type of altimeter setting that tells each of them how high they are above sea level. Accordingly, most pilots worldwide don't have any need to understand Q-codes; most of the world wouldn't know what QFE means and for God's sake of course I'll never use it!!
