As you read in all reviews, this flat is great indeed!
We had a great time in Valletta and we loved the house, but we weren't satisfied with our choice for the following reasons:
1) We never met our hosts and there was no interaction at all with them. This is what makes air-bnb special for us. It was just like staying in a hotel.
2) Communication was not personal. We asked for details on how to arrive 3 weeks beforehand because we needed to have everything organised. Anna booked a taxi for us and we thought that was all but 2 days before our arrival we got a huge message with all the info on how to arrive & enter the flat. (We were getting married and it made it a bit harder for us.)
3) Internet signal was pretty bad in our room, it worked quite well in the shared kitchen though.
All in all, a positive experience but we wouldn't go back because it was too professional for us. Even hotels have personalised service for honeymooners - we didn't even got wishes through an e-mail. We felt like customers and not like guests.