Love it!
I've tried Bovril too but Marmite is stronger amd definitely has the edge. I had some on my toast for breakfast this morning actually.
Now, my wife can't stand it. For an additional data point, she's American and I'm English.
Interesting side note. I've heard that eating Marmite discourages mosquito bites. Certainly I don't get bitten when I've eaten Marmite before working in the yard. Noramlly I'd get bitten withing 20 seconds of stepping outside.