The Host
Sean's place was nice and cozy as advertised. The room and the entire house was well kept. Sean was available when we needed him and gave great recommendations for food and where to go for St Patrick's Day. He welcomed us to hangout in the living room, grab drinks from the fridge and pretty much use the house as if it were ours. He also left some water bottles in the room and restaurant discount cards upon arrival which was a nice touch.
Travel from Airport
If you take the bus from the airport (€12 for a two way ticket) to the last stop in Dublin, his house is about a 12-15min walk from the bus station. You can also grab a taxi from there to his house for about €6. If you do this,
make sure to have cash on hand as some of them don't take cards. Considering the fact that the bus ticket was only €12 for both ways and we had 4 suitcases and 2 bags, we decided to go with a taxi.
Location
City center is in walking distance but his place is also one block from a main road where you can easily track down a taxi if you don't want to do the walk. We did both depending on our schedule and never paid more than €8. Also, we decided to do a bus tour to the Cliffs of Moher one of the days and his house was a quick walk from that pickup spot. The Guiness Storehouse was probably the farthest out of our way but even that was only a 20 minute walk. Needless to say, I would consider this location very central for anything you were looking to do in the area. If you're looking to only walk and not use any type of paid transportation methods, it can be done. If you hate walking or are open to paying to get from place to place, you can take a taxi for very cheap from Sean's house.

Recommendation
This was my first experience using AirBnb and I had some concerns/reservations about living in someone's home for a few days but I was blown away by how welcoming Sean was and how "at home" we felt while staying there. I would highly recommend staying here to anyone visiting Dublin and can only hope that my future stays at other locations are just as great of an experience!