re: In your opinion, did OJ kill Brown and Goldman?

Yes, based on the blood evidence, which even members of the defense team were bothered by. It is very far-fetched to think Fuhrman planted OJ's blood at the scene, Goldman's blood in the Bronco, and Nicole and Goldman's blood on OJ's sock and place the sock in OJ's bedroom.

The defense did an excellent job putting just enough reasonable doubt out there, mostly centered around the gloves and Fuhrman's racism, to avoid conviction.

I would highly recoommend watching ther FX series, "The People v. O.J. Simpson: American Crime Story", which is now on Netflix. Gives great insight into not just OJ but into the minds of the lawyers and their tactics.