I really liked this hotel. From the moment I stepped in, the clerk at the front step was very friendly (in a genuine, reasonable way) and helpful, and the entire lobby area was thoughtfully decorated - didn't resemble your run-of-the-mill chain hotel. The room was spacious and quiet. The bed was comfortable and the bathroom was good. There's a really nice rooftop terrace. It's not fancy, but it's quiet up there and the wifi worked quite well, enabling some work on the side. I would definitely book this hotel again.
Also, San Telmo is a nice area with some museums, and lots of great cafes, restaurants, bars, pubs, and so on.