The inclines are one of the must-visits in Pittsburgh. I've only been on the Monongahela Incline at night, when Pittsburgh is beautifully lit. This incline is also conveniently located next to a T station, so if you take public transportation, this incline might be easier to access than Duquesne.
The ride is great, and the view at the top is unbeatable, especially at night. There are also lots of shops at the top, including an ice cream place (Dilfiore's).
Note: The incline is run by the Port Authority, so if you have a ConnectCard, you can use it here.