I Borg, on the surface, is a great episode. But, unfortunately, it started the Borg down the slipper sloap of ruining the best thing about them; the Zombie angle. I think what made the Borg so cool was the fact they were going to come for you....and there was no way to barter with them because all individuality was taken away once you were assimilated....
Descent is just an awful episode that ruins the Borg, and made them just another DORKY villain, and also ruins Lore, turning him into a baffoonish bad guy.
Rob