The flat is perfectly located, with metro station, museum and shops at its doorstep. We almost never used public transport since it was really close to the city centre. The flat itself is huge, with high ceilings and unique design. Our room was spacious, too, with enough storage space for us.
The bed wasn't so good though: it had no bedhead and the matress was a bit short, so we kept losing our pillows and my bf found his legs sticking out sometimes (he's not tall). Overall, our necks and backs didn't feel good in the morning, so I believe the bed could use some upgrade.
The kitchen was a bit chaotic but had all the nessessary amenities. Overall, we had a very pleasant stay and a good time in Naples :)