THE GOOD: MS from almost all Gundam series/movies/etc (at least the animated ones sans Endless Waltz). A high replay value. Pilots are not bound by series MS. (Traditional in G Gen, marvel to new players) Good battle scenes
THE BAD: V2 Gundam's Wings of Light not in the game. This won't reach US shores any time soon.
SUMMARY: A great strategy from the SD Gundam G Generation series is what SD Gundam G Generation Advance is.
MS from all current animated movies and series, excluding Endless Waltz, can be used in a war setting that pits basically the good guys of all Gundam against the bad, with the series' storylines clashing about in a masterpiece.
G Generation Advance's map is set like a tessellating regular hexagon, where six units (of which three MS can form a squad. One squad equals one unit.) are able to surround one enemy unit. This leads to capture possibilities, or a quick beatdown of the enemy unit. A very fun map to utilize, if not awkward at first for the new player.