Both are awesome games. I pick hobbit. I own hobbit over GB after going through the same decision last summer. After playing both courtesy of my buddy with a GB premium, I have fun with GB, but the hobbit blows it away in most aspects. It really is different than any other pin. Don't listen to the people that say it's slow. They haven't played it set up in a home environment. Hobbit goes nuts, then slows down, then goes nuts again.
IMO, both machines are beautiful. Hobbit is built solid and feels much better than gb. I would like a GB premium someday possibly, but after getting deep into hobbits code and constantly repeating gb linear code, I made the right choice with hobbit.
Last thing. I have 3 young kids. My kids ages 7, 9, and 11 fully understand the hobbits rules and love it. They did not like GB nearly as much, and were frustrated with GB when they played it. Just my experience.