My choice too. Those 150g bags can be done in a sitting if in the mood. Special mention for Prawn Cocktail Pringles and Pipers Longhorn Beef.
https://www.theguardian.com/commentisfree/2010/apr/05/charlie-brooker-world-cup-crisps That should have been brought back for every tournament since with a crisp flavour representing every country.
These were your boys and damn fine they were too. As far as I know, no longer available so that leaves Seabrook's Canadian Ham as the best crisps on earth bar none.
A few I enjoy Monster Munch pickled onion Salt and vinegar discos BBQ Bugles Ready salted Squares Giant Wotsits Seabrooks Prawn Cocktail McCoys Thai Sweet Chilli
Trouble is with threads like this is that we can't really make anything like a definitive judgement unless we've tried every type of crisp in the entire world!!!!! Still Mackies for me based on recent experience and a relatively small research sample.
Why has nobody made a gravy flavoured crisp? You could argue beef is close but just a chips n gravy flavour would be nice! I totally didn't get this thought from the OPs username.
I don't know if they still do them, but Walkers did a Thai Lime flavour (think it was in their sensations range). Otherwise Kettles sea salt, and once every few years a really primal urge for a packet of Frazzles!