Did not meet with David, the system is quite effective: I picked up the key in a password-locked box outside and just had to leave the key inside and close the door when I left.

So it's a perfect studio if you wish to be alone and have a more hotel-like experience (I did).
The studio is nice and big, pictures are accurate, and the bed & linen were great.
One downside, the carpet in the living-room/bedroom which sounds like there is a plastic tarp beneath it. And some drilling starting at 8:00 in the morning (but that must be exceptional).
The bathtub and bathroom are pleasant.
All in all, great location and pleasant flat in a central area.