When I was doing a lot of CW long-haul out of LHR, I'd get gate-upgraded to F maybe once in every five or six flights. But if it was a 747 and I had my usual 64A upper-deck seat, I'd turn down the upgrade and ask them to give it to someone else. Unless you're in 1A, I found the F cabin in the nose of a 747 to be way too cramped, and lacking the privacy you get in the upper deck windows. I usually skip the meals for night flights, rarely drink much if any alcohol on a plane, so none of those added F benefits were worth anything to me. And the seat seemed to be pretty much exactly what we had in CW as far as I could tell. And I wouldn't be caught dead wearing those silly pajamas on a plane or anywhere else.

So no, I never could understand why anyone would pay a premium for F on BA, until and unless the roll out they sort of F suites that Emirates pioneered.