GREAT location. Let's face it...you're gonna do a lot of walking while on "vacation". Their location happens to be within walking distance to lots of places -- 10 mins from plaça de catalunya, around the corner from the arc de triomf, right across from the Tetuan subway station, etc.
The only thing to take note of is this is a room in their apartment. You get a big room but share a bathroom with them. You can also use their kitchen & living room but if you're looking for more privacy then this isn't the place.
Otherwise, they gave us our privacy and we never had any issues with waiting to use the bathroom. There is no a/c in the room but it got really cool at night that one wasn't needed. Not sure how it'll be like I'm the middle of summer but in our upper 70F temps, it was nice.