Generally speaking, Obsidian are a better company than BioWare. Their games are far more morally complex and they enjoy a much higher quality of writing. They also give far more choice and control to the player, and trust the player's intelligence to a much greater degree. BioWare were awesome when they used to do this, but they stopped doing that somewhere around BALDUR'S GATE II.

KotOR 2 is interesting because it thoroughly deconstructs the STAR WARS universe and mythos, pointing out the flaws in the concepts in a thought-provoking way. The suggestion that there is no such thing as a 'light' or 'dark' side of the Force, only a force of nature which people can abuse or treat responsibly depending on their own choices, is quite subversive by the setting's standards (though murky enough to give George Lucas a heart attack). The way your crew is REALLY dysfunctional (rather than cutely dysfunctional-but-they-can-pull-together-when-needed, as in say KotOR 1 or something like FIREFLY) is also quite satisfying, especially the enraged-and-definitely-not-cuddly Wookie.

Where the game falters - apart from the whole 'not really finished' - thing is that Obsidian failed to subvert the STAR WARS setting whilst also creating something that was fully part of that setting. When Matt Stover did something similar in the novel TRAITOR, he still created a book that felt like STAR WARS (complete with one of the most impressive lightsabre duels ever). KotOR 2 often doesn't feel part of the STAR WARS setting at all. What BioWare did do better in KotOR 1 was nail the atmosphere more completely and perfectly, and also pull off a twist the equal of the one in EMPIRE STRIKES BACK. I have to give KotOR 1 the nod in that department, which is a shame because what KotOR 2 was trying to do was far more impressive. They were just prevented from pulling it off by LucasArts for reasons never fully clarified.