After 5 weeks hiking the Camino del Norte, the seminary is perfectly adequate, with facilities that are cleaned daily, clean sheets provided for bed, a restaurant and washing facilities in the basement. It's in a lovely location and the building is historic.
The main issue is the acoustics of the building and other travelers who ignore all the signs asking for quiet in the sleeping areas and silence after 11pm. Unfortunately, it only takes a few people to wake you up every couple of hours with either banging doors or talking loudly in the corridor (or on mobile phones in rooms - it's easy to hear through the walls, even a few doors down) to really ruin your stay - not being able to get any sleep makes everything else seem worse than it is.
The staff were helpful, though, and the seminary is in a great location to find local markets, the Cathedral, Park Almeda and other great things to see and do once in Santiago.