Sports games. Not my forte. But it is my 185th completed game. On with the analysis.
Game speed completion: I'll have to take everyone else's word that it took them 5-8 hours. It took me 12-15. It probably is easier than I made it out to be. I had chosen to avoid the story mode and artificially made the game completion longer. The game has a story mode worth 320 points when completed. If a player decides to play the story mode first, all other supplemental achievements could have potentially been unlocked throughout the duration of the story mode, reducing any achievement cleanup for full game completion.
GSL Potential: The GSL potential is high for this game. The game has already been recognized as a quick 1000 point retail game. Because it is such a high visibility game, what particpants will be looking for is if other competitors have this game on thier game lists to predict fast point potential. Because there is no game save capabilities, there is no way to stack points in this game.
What the guides don't tell you: Play the story mode first. Then clean up whatever achievements you did not unlock after the story is completed with the unlocked teams. The provided guide and roadmap in x360a will successfully walk the player through the story mode in the most efficient way. Expect the game to start difficult but get progressively easier as you add team captains to your own teams you beat them.
The guides tell the player to use directional up and the A button to hit the ball. Rather than that, use B instead for consistently better results.
What I found is that games go faster for me was if I could simply build the 10 point gap within the first or second inning. This was done after the second win and gaining two five star batters. If the game did drag into a third inning, I would quit and retry. But for story mode, the game was set to nine innings because you will need the extra innings to meet mercy rule requirements with the weaker team.