My wife and I visited Bellinzona as a day trip from Lake Como in September 2017. We visited the uppermost castle first, enjoying the views up and down the valley. From here we drove down to the middle castle, where we left the car to explore and walk down to both the town and the lowest castle.
All three are in good condition though as others have mentioned, they've definitely been "enthusiastically" restored in places. We definitely enjoyed our visit though!
As a side note, it's incredible how Italian this area of Switzerland is, we really couldn't tell that we weren't in Italy at all!
