The fact that it has the word "hostal" made me nervous. When I think of a hostal, I think of dozens of twenty- somethings smelling like smoke, drinking, singing, sharing bathrooms and/or bedrooms, and being loud. That's NOT the case at all at Royal Cruz.
Tiny rooms with tiny private baths and respectful neighbors. The staff seems to take the job of keeping it as peaceful as possible quite seriously. That being said, I would NOT book a room with a balcony. The street noise (not Royal Cruz's fault) can go on past 3 am. The narrow streets lined with 4 story stone/brick buildings form canyons that carry noise. ANY hotel room facing the street, not just Royal Cruz's, would have the same problem. Book an interior room, think skinny, and you'll do fine. Very convenient location