Compact, efficient ...but not cramped. We stayed for a month and never got tired of the apartment.
We explored Indautxu thoroughly and found loads of great bars, restaurants, cafés, stores, etc.
We enjoy walking, and the location made trips to the Casco Viejo, San Mamés, Arriaga Theatre, the Euskalduna, San Francisco district and the Guggenheim enjoyable and interesting.
Would highly recommend it if you like to explore the city on foot.