It appears that Bagwell and ARod were/are the exact same hitter:

Check out some other interesting comps after the break (All data from Rally's WAR database).

Mike Cameron and Johnny Damon were both born in 1973 and broke in as rookies in 1995.

Here's a few other spot-on comps:

(Chipper, that is.)

Now for some defense. In his 9 best seasons, Griffey Jr. saved as many runs as Dunn has given up during his career (Defensive runs is the sum of TotalZone + OF arm + Position adjustment):

Finally, Rickey Henderson gained as many runs with his base-running as Harmon Killebrew forfeited with his glove: