There was a smell of smoke and perfume that lingered in the flat for the three days I stayed there. Also, the bed is an extendable couch (at least in the app it says "5* bed"); Nollnot super-comfy. One night the warm water did not work, but that was fixed very quickly and can happen everywhere. That I had to install an app to get the code to the apartment seems overkill, but is also practical since the apartment can be locked/unlocked via the app remotely.
Bottom line, worth the price, but not perfect.