I read that the NZ Marmite (the Sanitarium bottle) isn't exactly the same as the UK Marmite (the first post from OP)
I just bought a jar of Vegemite over the weekend to compare against UK Marmite. My wife, who is from Ireland, had never had either - though she is familiar with Bovril.
I spread it thin on a cream cracker for her. It was as if it were made if ipecac... one bite and she was running to hurl.
Personally, I thought it was "ok".
I like Bovril, though. Nothing like a warm glass of beef tea.
Too bad there is no Bovril-like product made from bacon!