Conclusion: Handhelds usually do not have a lot of strategy. Yes, RTS and TBS sometimes occur, but these are usually only a small addition to other games. However, it is worth sometimes to throw a look at them - Advance Wars is one of the best turn-based strategy for the Game Boy Advance is a very good title, worthy of 8/10. It is worth to play. The first game of the series AW is a great, joyful entertainment, and it started a long series of great games.
Pros: Advance Wars is turn-based strategy, quite similar to Battle Isle series, where we are fighting with the enemy, and gaining buildings providing war funds.
Cons: The game has no disadvantages, unless you compare it with games from big platforms. Very small minuses are squares - I prefer hexes strategies from PC - and repeated battles animation. Sounds are average - but that's the charm of the GBA games.
Summary: Excellent. This is the best Gameboy game I have played in a long time. You can battle enemies, bosses and even make your own maps. Battle with a friend, play as your favorite character and SO much more. Buy this game if you have a Gameboy. It's an awesome game.