Guinness, room temperature or cold?

[beloitpiper]

So that's why it does not taste as good as draft in Dublin.

Yeah, there's a few differences between the Guinness in North America and Irish Guinness. First of all, Guinness in Ireland is about 4.2% ABV while the stuff in the US is 6% ABV; also Irish Guinness is unpasteurized while American Guinness is; another factor is clean lines, if the keg lines are not cleaned and the stout just sits in the lines the Guinness will become bitter, but in Ireland, where Guinness is drank a lot more frequently, the lines clean themselves due to the beer constantly running through them.

All of these factors contribute to a different tasting stout in the US.