I've owned both. GB was a dream theme for me, but the ruleset got boring quick. The flipper gap was frustrating because way too many cheap drains because of it.
Star Wars has a much better layout and more exciting shots to make. I am a fan of the code because it's more dynamic and doesn't feel like the same exact game on each plunge like GB.
I am not even a big Star wars theme fan and absolutely love Ghostbusters - and I'll tell you to get SW instead. GB the pinball was a total failure which was a bummer to me.