Two of us stayed in the flat for three nights in January. The location is brilliant with all the good spots within walking distance and a lot of cute restaurants around, one of which is Tasca Mastai, just round the corner and a huge glass of delicious red wine is 3 euros!
I can confirm the issue with the shower curtain has now been resolved - there is a door in place. Shower gel and shampoo provided as well as two small towels each which was a great help in terms of what to pack in the hand luggage! Going in January meant that the flat was quite cold but there are two heaters which warmed the place up nicely.
I definitely recommend this flat, loved it!