The apartment's location really is nothing short of fantastic. Walkable to Las Ramblas, the Mercat de la Boqueria, the beach at Barceloneta, the nearest metro stop is under 100 yards from the door, and you're right in the heart of El Born.
Be aware that El Born can get very noisy late at night on weekends, but that's the cost of staying in the hip gothic quarter/el born area -- which, again, is exactly where you want to be.
I found the 2nd and 3rd bedroom's beds to be a little stiff, but otherwise the amenities and location of the house were an excellent value even if we'd paid hundreds more than we did.