Quoted from Tuna_Delight:TBL has a cool upper playfield that looks like the bowling alley's parking lot from the movie. Between the perimeter orbit loop shot, the stand-up handicap parking targets, the reward shot, and the Dude's car bash toy that swings out from inside the building at various points in the game, it has a lot going on up there!
I second TBL as the best upper playfield. It's also very important to game play. You can trigger a bowling event in the lower playfield, start one of three game play modes, and it includes a bash toy.