Javi was a great host and has a truly beautiful apartment. All the reviews are really accurate and it is a wonderful place to stay in Vienna. You are so close to the centre but get the feel of living like a local in a cool neighbourhood with shops/restaurants/Ubahn all walking.
We took the whole apartment for Christmas and it was perfect for what we were looking for. Javi is a really cool interesting guy also. His interior design reflects this.
The only criticism I can make is in regards to the size and comfort of the bed. Admittedly I'm a pretty tall guy but I struggled to fit in the bed and mattress wasn't great (sinks in) so didn't have the best of sleeps. Having said that I would still come back to this fantastic apartment. Big thumbs up!