Let me start off saying that Valeria and her husband are probably one of the best hosts you will ever have a pleasure to meet. Valeria is always ready to answer your questions, help you with any problems you might have and recommend places to see or events to attend. Her husband helped us a lot when we screwed up leaving the keys inside the apartment (in the lock to make things worse). Always super nice and always willing to help.
In terms of location, it depends on what you want or need. For us it was perfect as we like to be as close as possible to the local way of life and the atmosphere. Everything is REALLY in close proximity to the apartment - the stores, the sea, the monuments, museums, literally everything. For us it was really cool. You can simply smell the history of the city in this area.
HOWEVER, if you are going to work in the apartment and/or need peace and quiet, this might not be the choice for you. The neighbours are pretty noisy. 100% true to the game local people, very polite but you are definitely going to hear the beautiful Sicilian/Palermitan dialect a lot and it's going to be loud. It may go as deep into the night/morning as 5 a.m., music included. The children may also be pretty annoying as they kicked/punched our door a few times a day for like 75% of our 2-month stay. Mind you, it was summer, so they weren't going to school during that period. I suppose it may be better the rest of the year.
The apartment itself is OK, it's spacious and 'fits' the neighbourhood in terms of the way it looks. You will find everything you need for a longer stay: cutlery, utensils, vacuum cleaner, iron, stuff like that, really all those things. BUT, you must remember that it's really dark in there. The daylight basically doesn't get to the apartment so when you are inside the lights have to be on the whole time. It also gets really hot in the summer so the air conditioning has to be on as well which makes it barely possible to stay within the 30 euro electricity budget. You will probably have to pay extra as we did.
The internet connection is great, it's fast and reliable.
To sum it up, I really recommend this place. If you want a full Palermo experience and a bag of great memories for the rest of your life, that's the place to be.