AMAZING. This is the best Airbnb I stayed in during a Europe trip of over one dozen cities. The building is secure and perfectly located, the apartment is immaculate and stocked with everything you could possibly want, and the hosts are very kind and considerate. Book this without hesitation; you won't regret it. I have no complaints.
Only thing to note: I traveled with a backpack so the stairs were not an issue, but it is on the fourth floor, so perhaps inquire as to whether there's an elevator if you'll be traveling with a lot of luggage.