Well, been there done that. 3 weeks, *Great* time!!!!!
But on topic, I whole heartedly recommend
Hostel Meridiano .
First, friendly helpful hosts as previously stated. Great accomodations, everything is new. Free internet access. Quiet. Great rates.
Location is ideal. Centrally located, you can walk everywhere interesting within a half hour tops.
Being next to a police station is kinda nice. Also next to a nice park, which has reserved parking for the police. So there's a 24/7 police guard walking the location. It was always nice to sit in the park after a long day regardless of the hour not worried about "security".
Next to the Meridiano is a great tapas bar. It became one of two favorites for the tapas.
Friendly, new, afforable, perfectly located, secure, with its own park and tapas bar.
You won't be disappointed.