Disappointing in the fullest. Spend your money on the PC version.
Sure, it has everything a basic GBA Fifa game should have: Quick Match, Career mode, Tournament mode, some challenges, and multiplayer capabilities with a link cable. However, presentation is very poor. Let's start off with actually playing the game. The pixelated graphics are what you first notice about the game. This may be forgivable, this being just a GBA game after all, but it really spoils gameplay. All the players look the same, except some differences in hair colour.
There may be a career mode, what most players would select at the start, and a tournament mode, which allows players to choose from over twenty knockout tournaments to play in. However, what is really bugging is that you cannot have both a career and tournament file saved simultaneously. Given that the career mode is five seasons long, this means that it will get really boring a couple of seasons in (especially since you keep winning anyway), and it is very tempting to simply delete the career saved file and start a new tournament.
Gameplay is very easy. After just a few games on the easiest and default setting, Beginner, you will find yourself thrashing the weak AI with ease. If you play the game regularly, you'll eventually find even World Class is too easy for you. The problem with the AI is largely the sheer ease in scoring goals. After awhile, you'll start using the same tactics over and over again to score, and it gets horribly easy, AND boring when you top the league convincingly every season.
There is also the Challenges section, which are a certain preset situations you find your team in, and the challenge is normally to keep your lead or manage comeback wins. For example, you may find your team 2-0 down after half time, and it is your job to win the game. This is rather good and interesting, and provides a form of break off the career mode, but there are only around 20 challenges for you, and as mentioned before, there is not much difficulty in the game.
There is not much going for Fifa 07 GBA in the sounds section either. As Fifa games go, they have tried to inject a few soundtracks that will be played in menu screens like the startup screen, but there are only a few, and it gets repititive and boring pretty fast. During a match, there is simply repeated muffled crowd noises playing that aren't all that exciting or inspiring.
Overall, Fifa 07 (GBA) is an overly easy game that will have you bored after a week or so.