I would recomend it anytime: very clean, comfortable, close to main highlights in Palermo on foot; apartment well furnished, kitchen clean and well equiped, basic things for breakfast too; every detail you could think. I did not need such a big aparment, but it can acommodate at least six people easily.
Comunication with Stefania and Paolo was perfect and fast. The option to transfer from and to the airport is an added bonus.
I would return to Stefania's aparment if I go to Palermo again.