The best of the apartment is, of course, the location. Everything is within walking distance: O'Connell Street, Grafton Street, Trinity College, the river, etc. Even with kids, it cannot be better in this regard. The supermarket in the ground floor of the block with liberal opening times is also very helpful if you have children who often want to have dinner at bay.
As for the apartment itself, I must say that it is a bit small for 4 people and the beds are not specially confortable (the sofa bed deserves barely the name). Also that there is practically no place to unpack (which is awkward). Ideal for just two people. Otherwise we found almost everything in the kitchen to cook, working properly, and a wide bathroom.