Nothing bad to say, except that 1) the onsen was often occupied, but that was probably because I tried going there 3 times a day, and 2) I have had much better food at other ryokans. I'd try it just once, and then get dinner/breakfast at Takayama's amazing restaurants the other days.
This was absolutely fantastic in every single way. The location is great, right next to the Old Town. The facilities are charming and old-fashioned, but clean and functional. The onsen was amazingly comfortable. The staff, however, takes the cake - especially the little old lady who runs it. She was a sheer delight, and made us feel right at home! Definitely returning here.