What would you like to receive that you would not buy for yourself?

Usually incrementally better slightly in every respect. To compare BA Club World to First for example… -Check-in has its own private security lane at Heathrow that leads directly into the lounges (you do need to walk through one lounge to get to the true first class lounge) -Concorde Room (BA’s lounge for First passengers) has true sit down dining with waiter service and a full staffed bar as opposed to self service. Not all outstations have the same amenties as Heathrow but some airports do have dedicated First Class lounges still -Boarding in the first group -Seat a little bigger in length and width (this has narrowed in recent years as Club World seats were introduced in 2019) -Better crew to passenger ratio and less toilets per passenger (especially now that First is only 8 seats on almost all aircraft, used to be between 12 and 17 depending upon the aircraft) -Dine on demand, and IME usually as much as you want within what is catered (BA doesn’t over cater First as much as they did 10yrs ago) -Premium champagne and wine, such as Laurent Perrier Grand Siecle, Johnnie Walker Blue Label -Better standard of food, although this is slightly subjective… -For arrivals into Heathrow where you can use the Arrivals Lounge there is a small breakfast room for First passengers with waiter service, plus you have the option to use a bath instead of a shower in the arrivals lounge (though the staff usually dissuade you because it takes a long time to run it, I.e. they don’t want to clean it) -More BA Avios earned and more points towards earning/maintaining status