Ghostbusters could be the best pin ever! But so could Medieval Madness, or Avatar, or High Roller Casino or any of the other 100's of Pins out there. It depends on what YOU enjoy.
"Best" is an opinion, and everyone has their own opinion. Perhaps ghostbusters IS the best pin for you. And that's great. I just got mine, I think it's a blast; and I'm happy to meet others who feel similarly.
For me, I don't have a "best pin". There are so many to choose from, and I really appreciate the VARIETY out there. For example, I would not want a Stern Wrestlemania Pin in my collection- and the pinside ratings would tell me it's not as well rated, but when I find one out on location, i feel compelled to play - partially because I have fun, and partially because there are so few out in the wild, I want to take advantage of it when I can.