I wouldn't put it ahead of any of the other courses mentioned here (I don't know about Portmarnock Links), but Royal Dublin, while not a favorite, is worth playing. It's flattish and the views are of the docks. The industrial vistas color a lot of the reviews, I think. It has some good history (site of Irish Opens, home of Christy O'Connor, etc.), is quite welcoming to visitors and is the only "Royal" in the republic. And it has some challenging holes. It's had some work done lately, on the bunkers mostly, as I recall. It's principal virtue is being close in--not a bad way to spend an afternoon at all.