Great hotel, good view from the room at the city. But even better (actually amazing) 360° view from the rooftop, including of course towards Merapi.
The room is good, there is a nice pool on the rooftop, as well as a good bar. No pool towels, though.
The gym is very small and has a funny triangular shape, was a bit overcrowded with only 6 people at the same time.
Only downside was the breakfast, fresh omelette was good, but some of the sweet bakery goods among the most tasteless things I've ever had.
That said, still a great hotel with a nice art focused lobby and friendly staff. Would recommend.