Well definitely not from a cask, craft brewing is a pretty dead art in Ireland due to the devil called Diageo. The typical bar here serves Guiness, Heineken, Carlsberg, Budweiser, possibly Budvar, and Bulmer's Cider.
Usually I'd be drinking a Guiness from a nitrogen tap for sure, but if you get the old-school Guiness Extra Stout in the conical pint bottles (no widgets etc) the head still stays for the whole pint when you pour into a pint glass. Same with a Murphy's. The difference is that the extra stout is a lot airier, like the German dark beers. I'm actually from New York, lived here for 2 years and getting into homebrewing because its kind of a novelty here.
The art with Stout is also partly in the pour. Finding a barman that can pull a proper guiness and you're talking about a completely new beverage from the flat, instant coffee flavoured, sludge that often passes for the black stuff.
BTW wasn't knocking anyone's brews. I'm a complete noob, and if its still tastes good, drink it!