Me and my wife travel to Catania quite often and this is definitely our favourite place. The flat is extremely clean and comfortable enough for even a long stay. It is not very close to the old city centre but conveniently located near the 'new city' centre and the motorway (perfect if you are travelling by car). There's always plenty of (paid) car parks available on the street.
The host is also very nice and helpful. We received complementary water, fruits and paste di mandorla on our arrival.
The only downside is that there is no lift and the stairs are tight and the apartment is on the third floor, but everything else makes up for it.