I've had the remote for about a week now. It does work with the PS4 Pro, but there are two things I'm still trying to figure out.
1. It does not turn the PS4 pro off properly, happened multiple times
2. When the PS4 pro is being turned on by Harmony remote you have to press the PS button on the dualshock controller in order to use the Harmony remote. I can navigate the Netflix app on PS4 pro but will not work on Amazon Prime's video app (not sure if it's the app or the remote) and when the remote is connected to the PS4 pro the LCD on the Harmony has the PS button, triangle, x, circle, square and none of them works except for the PS button, but works great on my other electronics. Hope this helps
BTW I have the Harmony elite with the hub