We had a good stay in Valetta with Valhalla! The location is perfect for exploring the city and ferries as well as buses are reached easily. The bed was really comfortable and the possibility to wash our clothes was appreciated. However, our Wi-Fi was not working for the first days, which was fixed quickly after contacting the responsible people. Moreover, the shower was floating due to its construction (mainly when using the rain shower), which was a little pain.
In general, we were really happy with our stay at Valhalla and would recommend them!