the DS has large robots too! but still, it's very much so a different kind of game. think of it as FFT is to the mainline.
and the best starting point would be the two localized games on the GBA. route you pick on the 1st i'd say depends on what you want: characters more focused on the story than themselves with a coming-of-age kind of vibe (Ryusei) or the veteran pilot squads who are much more awesome but matter less to the initial story (Kyosuke). both ways, you'll NG+ the other route, but i personally say the latter's a better starting point if you need to be sold. if you can deal with the standard shounen of high school kid turned mech pilot, then start with Ryusei.
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The King Wang.
Listen up Urinal Cake. I already have something that tells me if I'm too drunk when I pee on it: My friends. - Colbert.