Well, this is an interesting question because Tim Duncan should be labeled a Center but because David Robinson was on the team when he came in, he moved to PF. I am going to say Karl Malone is the best true Power Forward ever. While I do think Tim Duncan is a better play than Malone, Duncan is viewed more as a Center than a PF now. Look at all Malone did in his career:
2X NBA MVP
Voted in 1996 to the NBA's 50 Greatest Players list.
Voted to 11 All-NBA first teams, two second teams and one third team.
Voted an All-Star 14 times. MVP of the All-Star game in 1989 and co-MVP in 1993 with Stockton.
Voted to three NBA All-Defensive teams and one second team.
Malone was ranked #13 on Slam Magazine's Top 75 NBA Players of all time in 2003.
Played in 1476 games, averaging 37.2 minutes, 51% shooting from the floor, 74% from the free throw line, 25.0 points, 10.1 rebounds, 3.6 assists, and 1.41 steals per game.
Recorded a record eleven consecutive seasons in which he scored at least 2,000 points. No other player has come close to this achievement.
His jersey number was retired by the Utah Jazz (#32) in Salt Lake City on March 23, 2006.
A bronze statue depicting Malone was dedicated on March 23, 2006 on the southeast corner of the EnergySolutions Arena block, next to the one depicting John Stockton.