There's a pretty big thread on Pin Stadium here, which contains a lot of before/after pictures. Check out the gallery at the top of the thread:
https://pinside.com/pinball/forum/topic/new-pin-stadium-lights-official-announcement
Me, I have Pin Stadium in my LotR and it's a day and night difference, especially next to my Hobbit with its bright LED lights.
That said, I'm not sure how much it will do in a JJP Pirates since that's already a pretty nicely lit modern game. Maybe someone tried it and can post a before/after pic?