Halloween for me - I ordered one based on the fresh and unique playfield layout. Much as I love the look of Godzilla, and I'm sure it will be an amazing game (especially being designed by Elwin he's a genius) - I might be getting a bit of Stern fatigue. I currently have XMen LE, Deadpool Pro (edit: literally just sold so I can upgrade to a premium), Star Trek LE, Ghostbusters Prem, Iron Maiden Prem, Avengers Prem.
I've played a few more of the recent ones too, and I dunno, it probably won't make much sense but they are just starting to feel a little "samey" even with Keiths incredible design and Yeti's amazing art. I really wanted to try something different for my next pin, and Halloween looks fantastic in that regard, plus I am a MASSIVE fan of the original movie so it was a no-brainer for me. I'm a sucker for artwork too, ZY is one of my favorite ever pinball artists, but my gosh Halloween looks absolutely amazing art-wise.
I'm not really sure these machines are comparable in terms of which one is better - but you are getting a brilliantly designed toy filled Stern on one hand and a very unique looking, cult movie boutique pin on the other. You are bound to gravitate quite heavily to one of them based purely on personal preference.