My husband and I stayed here for two nights. We booked a 'double room' which was in fact bunk beds, but that doesn't really matter. We were staying in Aix-En-Provence at a busy and expensive time of year, so we were grateful to get accommodation!
The girl at the front desk was not particularly helpful or friendly, and certainly didn't offer any advice about what was good to see in the local area.
Breakfast is at very strict times, and very basic fare (but, again, it's a hostel...), we were a little frustrated that you couldn't access your room at all from 10:30 until 16:30, and that reception itself was closed from 12-4pm each day. The bus to/from the city centre was, however, very good, and ran frequently until 7pm each night.
Probably the most frustrating part was there was a lack of facilities, no washing machines, no fridge for groceries etc. We were, however, really pleased that the bar decided to show the opening ceremony of the Olympics on a projector!
So - fine for a short stay, reminded us of school camp in terms of facilities and atmosphere. It's an expensive area to stay, and given that we ended up paying 26euro pp/night, I'm sure you could do worse, but I'm sure that if it wasn't the middle of peak season, I'm sure you could do better!