Guinness is better partly frozen

My recommendation is, for a can of Guinness Draught that has been fully refrigerated, you should put the can in the freezer for between 1.5 and 2 hours to get the full slushiness:



P.S. And it turns out that (at least for the freezers I've experienced) you can leave the Guinness in as long as you want, too. It might need to warm up for a minute or two before you try to pour it out of the can, but other than that, no problems were encountered. =)