I suppose both lounges in Dublin suffer from the fact that while they are both reasonably comfortable, if a little crowded at times, the range of offering is both limited and varies so little over time. It fills a brief gap, and has a bit of an Irish slant, but it's not a patch on the LHR lounges. It's not a long way different from No. 1 Traveller at LGW N, though not as crowded as that place can get. They are both close to the standard for European shorthaul lounges, though of course DUB does have long haul too. I'd probably still prefer the GC lounge slightly, it is a bit more modern and has a reasonable aspect, but without having seen the DAA lounge improvements referenced here, there isn't a lot in it.