Very pleasant and exciting experience. It's really a grand hotel and I got the impression, the host liked to show, hey, hostels and b'n'b-platforms, we also can do this, just a little bit shinier ;-)
Friendly and helpful staff.
And although the price of the optional breakfast approaches that of the accommodation, I definitely recommend it - a delicous and comprehensive rooftop buffet accompagnied with a really nice view over Vienna, the Ringstraße in the front, some of the Stephansdom in the back - that's how a day may start!