As a hungry adolescent during the war it was not rationed, so a welcome substitute for cheese in a savoury snack. I don't know how much salt there was in Marmite, mush too much perhaps, but with fresh toast it seemed very good at the time.
Mother made jam, and used sugar saved from our rations, so my brother and I did without in our tea and on any breakfast cereal.
The increased rations later pushed Marmite off the menu at home, but about 1953 I went with a group on a guided tour of the Bass Charrington brewery in Burton. The guide told me their surplus yeast was sold to Marmite for £15/ton.
As I said I enjoyed the stuff at the time, but I don't think I've had any Marmite for 50 years.
I occasionally add a half-teaspoon of marmite to a very big pot of home-made chicken broth or 'ham-on-the-bone' soup, to give it a kick ... I always treat marmite with the same care as I would nitro-glycerine!
There doesn't appear to be many Royalist's on the forum, who have suggested that Prince Charles likes nothing more than a few slices of fried bread with a Marmite topping (perhaps another one of those wonderful secrets?).
Just seeing this thread, as reminded me that we purchased a jar of Marmite a few months ago, and we had forgotten all about it. So a rummage in the back of the food store, and yummy yummy.