I stayed here while doing my internship in Crumlin. Julien was always very helpful whenever I had questions and the apartment is in a nice, family-friendly, and quiet area.
A word of caution - while Dublin is a very safe city, the area this apartment is located in can attract some questionable people. Just be sure to make smart decisions, i.e. don't take a stroll out in the dark late at night, expect some troublesome teens to annoy you here and there, don't take out any flashy gadgets.