So—after discussions in bars with several natives that had experience with the US version…
The canned version we get over here? That’s pretty much the same as Ireland; several guys told me they couldn’t tell the difference…but US draught should be avoided (in most instances—see below).
The problem with draught Guinness in the US is that unless you’re in a place that sells a LOT of it, it’s likely the pull you get will be nasty from turning in the line (lines in the US are much longer than overseas? Can’t confirm, but…seeing the size of some Dublin bars, it makes sense).
Also, most American bartenders don’t know how to pour it (if you want a Guinness in Ireland, order a half pint of lager—or a whiskey— to tide you over while you wait for the correct pour…again, as I was advised by the natives). It takes a couple of minutes for the initial pour, a period of settling, then topping off the glass…and waiting for it to settle again.