Ray Lewis.
Urlacher was much more injury prone. He also struggled when his DT play in front of him was not up to snuff. He was at his best when Ted Washington was in front of him. Then Washington went down in 2002 and teams could target him in the running game for a few years until Lovie Smith started to use him properly. There was one game in '02 (IIRC) where Chris Chambers, a WR, dominated Urlacher in the run game of all things.
Lewis played in 4-3 Cover 2, 3-4 and other types. And he really set the tone for the Ravens defense over the years. They had different head coaches and D-Coordinators, yet it seemed like Lewis played a larger role in developing defensive players.
Oh, and Lewis wasn't dumb enough to try and start a fight with Bas Rutten.
YR