And I've seen people ski park in Race boots...any boot can be used in the park, it's all personal preference.
Fullt Tilts boots may look the same but they are all very different, the 3 most important differences being the Tongue Flex (soft #4, mid #6, mid-stiff #8, and stiff #10), the boot board (Ridged boot board is a solid piece of plastic which offers more control between the boot and snow, and the Active boot board which offers a soft shock absorber), and the Liner (Performance is thiner, lighter and more breathable, while the Pro is thicker, warmer, and holds you in better). Other than that, some boots have cable covers while other don't, some offer metal buckles while others have plastic, some have metal cable anchors while others have plastic, and some have wider power straps than others.
It doesn't matter too much which one you get, cause you can always get different parts, but it is cheaper to just buy the boot that best fits you. That being said, the Booter and Hot Dogger are more geared towards park because they are softer, while the konflict, first chair, and Seth are more gear towards big mountain because they're stiffer, and the Classic (aka bumble bee pro from previous years) is gear towards all mountain cause it's a custom mid-flex, with a rigid boot board and pro liner.