Personal experience, but my least favourite of the above four. Food wasn't memorable. Our assigned staff weren't japanese, probably because we are english speakers. I would have been happy with phone translation as in other places.
I went to the river side public bath several times but it was always occupied. Maybe due to high season.
However, the onsen water quality in the room was best here. There are things to do nearby, we went to Kagoshima and Sengan-en garden afterwards and even saw the volcano eruption.


View from the room.


Onsen on balcony of the room.


Sengan-en park 30 mins before volcano eruption.


When we were just leaving.