I Borg was a good episode. As I said in the other topic, if an invincible villain race is made into a recurring foe, it's bound to be wussified.
If TNG had stayed on the air, we would have seen something like the Borg Baby and Unimatrix Zero (as Geordi or Riker episode) there, too. There is only so much you can do with an unstoppable race of mindless Cyborgs.
I, Borg was rather good and fit TNG very well.
Descent was a friggin joke.