The place is very clean and tidy, and Kieran was welcoming: he gave us a Dublin map and explained which places were interesting to visit.
The room is very small, so you have to be a bit organized with your suitcases and clothes, but that's well enough if you just want to rest and sleep.
You share the bathroom (shower and toilets) but Kieran was discrete, so it wasn't really a problem. The first day there wasn't any key for the bathroom, but Kieran looked for it and we were able to lock the bathroom after.
There is also a living room and a small kitchen but we didn't use it.
The apartment is not really in the heart of the city but red transportation line is about 10 min walk.