I have a Black Rose and have had it for 8 or so years, never going to get rid of it. Even though I have the game figured out to a tea and can regularly put up 300 mil + games (highest game was about 1.9 bil), I still love playing it!
Once you get that Whirlpool shot down, you can basically play forever. It gives you extra balls and lights multiball. Normally, I would consider this a bad thing, but Black Rose has so much to offer I don't mind getting infinite extra balls. The multiball rules are awesome, and getting three ball with hidden treasure is super satisfying. I'll post a picture at some point, love this game!