After just a few games on each, I lean heavily towards GB.
I would never have thought I'd see a Stern Pro at launch look better than a JJP LE, not back a few years ago, but Stern has really stepped it up. The GB package is beautiful. Great music. Nice flow. It's high energy. Wicked bounces, but nice feeling shots. The left ramp is a great shot. Slimer toy is very neat. Immediately immersive and just a sweet pinball package with easy to follow rules, and nice variety of shots.
Hobbit is very much the opposite. Low, low energy. Art is just the plain Middle Earth type art you'd expect. Random Dwarf song/music/axe clank every time you hit anything. Smaug is forgettable as a non-interactive puppet head (literally, you forget he is there...not joking). The trolls are just that...trolls, without the witty charm of the MM trolls. You wonder why such a big open playfield, and then you realize..."Wait, they did this just to fit in more trolls?" It wasn't worth it. Playfield is just a big open, low energy playfield, and nothing really draws you in. Now, I'm sure it's more immersive in a home environment, and the guys who ordered one for their gameroom will have fun with it as you find out how deep it is, etc. But there doesn't seem to be that 'arcade hook' at all. I walked away with no desire to return anytime soon.
Never would I have thought a Stern Pro would sound better, look better, play better and just be more fun out of the box than a JJP LE. But that is the case. It's less about Hobbit being bad, which it isn't...it's just there and less than you'd expect. It's more about GB being one of the best Pro packages Stern has put out, probably THE best. Admittedly, that's just my first impression based on limited play.