Emerald fiel was an average hostel, it serve its purpose as a place to stay and a rough idea were to go in the city. That said the staff was helpful to a minimum, our room did not have a key; their was no kitchen were to cook, the breakfast i also kept to a minimum (tea, coffee and dry biscuits) and we had to pay for the hostel to keep our luggages on the last day. Although the hostel is very clean, not allowing thos hosts to stay in the hostel between the hours of 11 to 14 is rather rude.
Mosaic Hostel was a fine hostel, we like the level of security and the friendliness of (most) of the staff. The price is high but the location is worth it.
Alfama's staff was very personable, friendly and welcoming. They also were very knowledgable about the city. The breakfast pancakes were AMAZING to the point that they were the main reason why I would wake up half an hour earlier. We would recommend the walking tour. We loved to have free access to destination hostel and enjoy there facilities (pool tables, relaxing lobby and bathrooms). The location is very central and has quiet a view night and day... We would for sure go back to Alfama.