Here's a player comparison that I found interesting - keep in mind that both players are 29 years old with not much big league experience:
Player A: 211 AB/ 30 R/ 13 HR/ 28 RBI/ .284 BA/ .890 OPS
Player B: 143 AB/ 26 R/ 3 HR/ 26 RBI/ .294 BA/ .873 OPS
The numbers are fairly close. Player A has more power but he also has a third more AB this season. The big difference is the hype around the players. Player A is Cubs prospect (and pride of Worcester) Brian LaHair while Player B is the vastly under-heralded Daniel Nava.
It is supposed to be the on the field performance that counts. It will be interesting to see if that holds for good guy Nava.