We have just come back from 4 nights here. The staff were all absolutely lovely (and, it shames me to say it, all completely fluent in English).
Considering that it was situated really close to the heart of this vibrant, diverse, beautiful and edgy city (10 mins walk from the station), the soundproofing was absolutely fantastic in our room (room 510 by the way).
Without a doubt, the best thing about this hotel is the roof terrace - absolutely jaw dropping views over Palermo and the surrounding mountains. You can spend breakfast (also served on the terrace) planning the day's adventures using the free wifi. And enjoy a nightcap here marvelling at Palermo by night.
They were also happy to look after our luggage on the last day - and also allowed us to enjoy the roof terrace one last time!
Honestly, could not fault this place.