Just returned from a 5 night stay at the Derglave Hotel. I visit Dublin often and try to make sure I review everywhere that I stay to help other people make the right choices too, as Trip Advisor has been so helpful to me in the past.
The Derglave Hotel is around 5-7 mins walk from O'Connell Street on the north side of Dublin, and around 15+ mins walk to Grafton Street.
The staff are friendly and helpful, and the reception area is very welcoming.
The rooms in reality are just as they look when you see them on the net - clean, airy, comfortable. I stayed in a single room which was fairly small to be quite honest but I had adequate wardrobe and drawer space, a comfy bed and a nice clea bathroom. I found my room to get quite chilly even though it was august - but not to worry as every room has a freestanding electrical radiator which gets the room toasty hot :-)
My only gripe with my room was my shower - the water often took up to 10mins to heat up, and the shower pressure was terrible, making it difficult to rinse the shampoo out of your hair. Mostly ended up showering at friends houses to save time as it was just so time consuming with the lack of flow!
All in all apart from the bad shower, the hotel was excellent value for money.