If you're even the remotest fan of turn-based strategy (or even tabletop strategy wargames, for that matter), this is a must-buy. I've played PC strategy games that can't rival the charm and depth of Advance Wars.
At its core, Advance Wars takes all the mandatory elements of a good wargame and condenses it. You get a tightly edited list of troops and vehicles -- there's not an extraneous unit in the whole game -- that subscribes to the rock/paper/scissors method of game balance. In total, there's about a half-dozen "commanders" that use the same units but get varied stats depending on their "strength" (e.g. the tank specialist gets strong mobile ground units, the "sniper" gets excellent long-range units, the "air" specialist gets great air power). While the unit list is fairly brief, the variety of commanders' strengths gives the single-player campaign and multiplayer lots of replay value as you try out different tactics on your opponent, depending on his strengths/weaknesses. Advance Wars actually reminds me a lot of Command & Conquer: Generals -- Zero Hour in this respect. The game rises above generic tactical warfare by giving your AI opponent a distinct personality.
Speaking of personality, Advance Wars oozes it everywhere. The single-player campaign excellently develops its characters and storyline (a strategy game with a story?!!!!) and is certainly worth playing through to the end.
Unfortunately, the graphics are very cartoony/anime, which -- personally -- doesn't fit the wargame theme. They do look good on the small GBA screen, but it does feel a bit odd to play such an in-depth strategy game with units that look like Pokemon characters. The sound is mediocre, as most GBA games are.
Overall, this is a huge game for your money, and while I haven't played Advance Wars 2, I'll take a wild guess and say you probably don't need to if you've got this one.
