The four best outlet passers in NBA history are probably Bill Russell, Bill Walton, Kevin Love and Wes Unseld.
Of these, Unseld is by far the most unusual.
First, he played center at 6-7 and this was in an era of legendary big men. During his career he played against Bill Russell, Wilt Chamberlain, Kareem Abdul-Jabbar, Bill Walton, Willis Reed and Nate Thurmond and more than held his own.
And keep in mind that for most of his career, the NBA was a much smaller league than it is today, so he saw those guys a lot.
It’s amazing in retrospect that he could fight guys who at times were a half-foot taller. He could do it partly because he was as powerful as anyone and partly because he was a smart, efficient player.
And he had a real weapon in his outlet pass. A powerful rebounder, Unseld could drop a pass in the hands of a teammate streaking downcourt near the other basket at any time.
Russell was probably the best outlet passer - he could do it while he was still coming down with the rebound - but Unseld was not far behind.
Take a look at this video and watch him just drop dimes on his breaking teammates. The guy was really something else.
Incidentally, Unseld is Love’s godfather.