I have had a TH for about 2 weeks now. The game is setup steep, no center post and strong flippers. People chiming in from having played this game a year ago at a show is a bit silly to me. The shots feel good to hit, especially the spinners. There are tons of shots. The game is super fun to play, the sounds are awesome, the use of the ring makes you constantly eye the button and the upper screen, the use of the playfield LCD for mode info is what every game (mode based or not) should have, learning to stack modes/postpone modes and locks is strategically diverse. I have had zero mechanical problems and my son has played it at least an hour plus per day since I received it. The game is fast, hard (remove the center post, duh) and not "floaty" at all. You can hit either ramp from either flipper to change mode, start mode, add time to modes or lock a ball, giving you huge control of how and when you play your modes and multiballs. The upper right flipper is used to enable short timed shots when the ball leaves the pop area or comes around from a left orbit shot. Given that its running .81 code (or whatever it is) its amazing to think where it could go.
I own plenty of Sterns and they are great, but about every new Stern is the "best game ever..." GB art looks awesome, no doubt. But no way to tell yet how good it will be to play. I think, at the end of the day, games live and die on code. most people argue that layout is king, but take TWD for example. People HATED it when the code was bad. Now, with good code, the game is great and well received - but, the layout IMO supersucks (I own TWD and do love it despite the shitty layout). Can't possibly hit the Riot shot from the crossbow...check. Tunnel shot is so poorly designed that most shots to it just rattle around to the right of the pops and never go around (folks, saying that you have to be perfect to hit the shot is not a testament to well placed geometry of a shot path)...check. Bicycle girl ramp is insanely steep and many good shots to it are rejected due to the design (premium only)...check. Ball in pops stays there sometime far too long, interrupting game flow and then sometimes goes SDTM...check. Game has awesome code and is fun nonetheless...check.
Who knows what issues GB will have. Put your order on hold and go play the games if you're not sure.