Me and my mother rent this flat in September for one week. And it would be perfect, atmospheric, if we wouldn't meet there big cockroaches. Isabella was really nice and made some disinfection, but it didn't help :( Maybe for some it's not a problem, but for me a big one. I couldn't sleep there and felt uncomfortable. Next time if i will have this problem, i will change the flat. I hope that this problem will be solved in a short time!
Shower was really small even for me, not good for big, high or fat people. Also Internet didn't work, but Isabella helped us with sim card with 20 gb internet, so it was comfortable to use outside for maps, etc. Transport in Catania is not regular (you need to wait the bus from 30 mins and people there in general don't speak English), so it will be helpful for you.
p.s. if you have a big luggage, its hard to take it from the bus-stop to the flat (we had 30 kilos in one bag). Also you need to take it from 0 floor to 1st.