I read a good portion of this in preparation for the trip my husband and I took to Ireland last month with our daughter. I haven't purchased any Rick Steves travel books before, but overall I did enjoy the way it was laid out with various recommended itineraries that vary in length. We only spent 5 days in Ireland, so obviously we weren't going to be able to do Steves' recommended 3 week round-the-country trip. Also it was January so...cold.
As with most travel books, I think everything needs to be taken with a grain of salt. The rigorous 2 day Dublin itinerary was something my husband and I could have done by ourselves but was definitely not feasible with a toddler. Some of the top Dublin recommended activities were a bit of a let down for us (for us, the Old Library was way cooler than actually seeing the Book of Kells, but overall I felt the entire thing was overpriced), but some of the lower ranked activities were some of our favorites (Dublinia and the Guinness tour were so much fun!).
One of my primary complaints was how much fluff I had to skip to get to the actual information on sites, tours, etc. Information on laundry, post offices, heck even hotels can be helpful for some, but can't that all be pushed to the back of the chapters? I'd be willing to bet that most people are looking at a book about traveling to Ireland to see how they should best spend their time, not to figure out where they can do laundry halfway through their trip. *Most* people have international data on their smartphone plans and can just google that sort of thing while they're there. And I highly doubt people are going to book a hotel purely based on a recommendation in a book without doing any other research. Again, it may be helpful, but it's just annoying to skip past all to figure out what I should do with my day in Kilkenny.
So, overall helpful for figuring out what activities we wanted to do, but I'm really glad we did some things that weren't necessarily top of the list, or we would have missed out on experiences we found really fun!