Sokol's place is great for 1-2 people visiting Athens. The location is close enough to walk to all the key sights, and close to psyri with many bars and restaurants. We did not use any public transportation and all and felt comfortable walking around during day and night.
We arrived quite late (3am), so we wanted a place with self check in. The lock boxes makes it very easy to do so, just be sure to read all the check in instructions. In addition, he arranged a taxi for us, which was perfect after a long flight. The taxi driver used a tablet to communicate in English and helped us up to the apartment. We forgot some items in the apartment and Sokol was quick to communicate with us so we could go back and retrieve them. Overall would definitely recommend!