Stayed here for two nights and it was really great - the street doesn't look like anything special but you are very close to the main area of San Telmo and the market so it was really great.
The apartment was really nice and bright and very clean, modern - just like the pictures! Felt very nice hanging out there and there was lots of space.
They also helped us arrange transfers to/from the main airport so that was really useful!! :)
Would definitely recommend if you want to stay in this part of town!