We enjoyed our stay here. The location of the apartment was very nice, close to the promenade (sea side/bay), with restaurants and cafes close by. The Sliema Ferries were only a 10/15 minute walk, which is little effort. The apartment was clean upon arrival (besides a stuffy smell in the cupboards), and the air conditioning is very nice. Also, WiFi is good. Small improvements could definitely be made; the couch was not very comfy and the TV was not working, but that was no problem for us since we were mostly outside.
The host was always available for questions and responds quite quickly. Our flight was delayed (2,5 hours) which gave us no time to meet Humbert. However, he clearly explained how we could check-in and also eventually check-out because we had an early flight.
Shortly, this apartment is good if you want to explore the island or the closer areas most of the day, but it may not be ideal if you're looking to spend a lot of hours relaxing indoors.