it's nice, would give it a 7/8. Nice buildings, felt save, and you are able to avoid the crowd if you want to. Felt not so special, but has all the Italian aspects. Good for all ages, except that there are A LOT of beggers and homeless people, gave me a feeling of guilt and it was quite annoying.
Insider Tip:go to a square at night, the locals do not really go out but gather outside with drinks and just talk, I recommend it! Good vibe, lots of fun. Had no trouble riding a bike in the centre, although you can also rent a segway (more expensive) and the walking tours are good.