Quoted from jar155:GB is probably the best game Stern has put out since AC/DC. They finally put together a game that provides a solid challenge where if you drain it's your own dang fault (assuming you have adjusted scoops, air ball protectors, etc.). It doesn't have any of Borg's silly magnets in front of bash toy nonsense, it doesn't have the same wide fan shots (despite being a fan layout), and it has skill shots that actually take skill and provide impact on the game.
Now, there definitely needs to be another couple of passes on the code. The linear modes aren't an issue, because they are logical in their progression and you can hop around the ladders if you want to. What is an issue is that the final wizard mode is basically uncoded, there are some bad persistent bugs, and the game could really use some combo scoring and make better use of the Ecto Goggles.
Ghostbusters isn't perfect at all, but in all of its imperfection, it provides a fair challenge that we're too often struggling to get in pinball these days. It feels like you're just on the edge of control the entire time, and it makes for a fantastic "one more time" game.
All that said, if an operator has one out on location and they haven't tuned it well, it can be a nightmare to play.
Amen on the combo shots/scoring. I never understand why some games don't have it, as they can be some of the most satisfying shots in pinball.