Pick between GOT or TWD. Skip GB.
TWD pro is one of best sterns ever IF...you like the theme, IF...you can swap out the sounds with pinball browser (plenty out there to download), IF...you like brutal games, IF...you don't mind cheap drains, IF...you have the patience to learn deep rulesets, and IF you like bash toys.
go GOT pro if you enjoy flow, speed, rules, more flow, multipliers galore, fun, and diverse strategies; at the sacrifice of a slightly more unpolished code and weak art package.
TWD is the better game by a hair, but only if you like that style of a game. GOT is consistently more fun and has quicker rules progression. Tough choice. Technical Rules + Depth + trap & shoot (TWD) vs Strategic rules + Breadth + flow & speed (GOT).