This hostel is conveniently located from the main square (Plaza des Armas) and Mercados area (the typical high - street shopping area). The local map they provided was sufficient for the nearby area, but if you travel further afield it would be wise to visit the tourism office in the Plaza des Armas for a bigger map.
The taxi cost from the airport was 20/soles as organised by the reception in the hostel - contact them ahead for airport pickup arrangements. It should be 8 - 10 soles for a taxi to the bus terminals. Give yourself plenty of time for taxis, Arequipa taxis weren't very punctual for us.
The rooms (booked a double room ensuite) themselves were clean and comfortable, towels and soap were provided. Ugarte Street is quite quiet at night so sleeping was fine. There is a row of computers for free internet access near the reception. They were very convenient and were of great use to us during our time at Las Torres. I have to admit that the hostel's wifi reception on my phone wasn't so good within Las Torres, but others may disagree when using a laptop.
The breakfast was the best I've had out of all the hostels in Peru! Omelettes, some puffed rice grain cereal, fresh fruit, hot beverages and sliced hams/cheeses with bread rolls -- great to eat a substantial breakfast. There is a nice terrace/balcony area one level above the breakfast area, the view of the city isn't bad from there.
The staff at Las Torres were amazingly helpful. We repeatedly had lots of help when booking bus tickets to Chile and organising an impromptu trip to the Colca Canyon (highly recommend, even if the 6hr-journey is a PITA) - helped translate the phone conversations and provided sound advice throughout. Very professional, very friendly, very capable. Would recommend you have some basic Spanish ability (we didn't but communicated fine) but it's not an issue as one of the staff speaks English, French, Spanish and also a little German!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.