I have all three, each one being bought after the other after the one before it looked like it was going to croak, though in the end, none of my DS(es?) have actually broken yet, and seem to work fine after I cleaned them all up.
DS (Original):
Dark blue color-scheme, complete with stylus and random GBA game to fill the GBA slot.
DSlite:
Dark blue like the first one for continuality, missing GBA slot filler, and has a scratch on the cover, but otherwise works fine.
DSi:
Light blue (yetch, I should have gotten the black one), with a miss-matched stylus that's of the wrong shade of blue because I lost the original AND its back-up.
And that sums it all up. All three see equal use, either when I'm trading between Pokémon games, or when one's battery dies and I'm too lazy to charge it.