Rose and Crown Pub also does a very nice Cider and Black (cider with a shot of black current juice) I usually get this when drinking around the world as my usual Guinness is a little bit to heavy.
Where do you get this in the Mexico pavilion? I usually just do a tequila shot, as the margaritas in La Cava, although delicious, can be a bit sweet when drinking around the world.
Best tip, as others have said, stay hydrated! On that note I also suggest using the restroom whenever you pass one, just in case!