I had one of my best nights' sleep in the Mada Guest House. Such a comfortable bed! The room itself was exceptionally well furnished, with a large TV with access to streaming channels, a couple of extra fleece blankets and a portable heater for those cold nights (Puno is very high up). In the winter months, from June to August, temperatures at night often drop below 0 °C (32 °F). There was lots of storage space, plus a desk and chair. The shower pressure was excellent, although there's not much room to move around. Breakfast was good, with eggs, fruit and fresh coffee.
The only downside is the location. It's tucked away along an alley and the signage is easy to miss. It's very convenient for the bus station - 5min walk, but a 20-minute walk to the Plaza de Armas, shops and restaurants.