Having read all comments, I wish to say that this is a 3 star hotel. Don't expect a 5 star one. The rooftop is excellent, with a nice small swimming pool and bar. Prices are not too bad for alcohol and food, 50% discount between 4 and 7 pm. The lobby is very modern.
Now, regarding the rooms: they are also modern. Bathrooms are just OK. Water is a bit smelly, no curtain in shower so inondated for every shower you will take. Sink also not well fixed. Bed is very comfortable. Not possible to open windows, so we could not get rid of the bad smell from the bathroom. However it is very clean.
Wifi is working everywhere. Breakfast is not too bad. Regarding value for money, I booked very early and I had a good promotion. A friend joined us and had to pay full price, ie double, so book early! I really really recommend the rooftop!!
Staff is really friendly, smiling and helpful.
Good to know: No possibility to have an extra bed in the room. Also, hotel was fully booked so my friend had difficulty booking: once more, book early! Location is good. Near Malioboro, though I didn't really like Malioboro. Yogyakarta is great though, lots of things to see and do. Kota Gede is awesome! (not the silver factories but the heritage walk).
Travel agent did not speak good English but was very friendly and we could book what we needed.