You can believe or not believe those weights, it doesn't matter. A simple eye test tells you that Fielder is WAAAYYYYY heavier as a 28 year old than Vaughn was in the mid 90s (and let's not ignore Vaughn's 2 inch height advantage). Most sluggers are thick in their mid to late 20s but generally, they're not fat. That comes as they age into their 30s (just like everybody else). Given Prince's weight at age 28, what do you think he's going to look like in five years? Mauer and Fielder are similar in WAR, despite Mauer playing half his games at first and DH, something I expect to see slightly less in 2013. Now that he has proven he's healthy again, I expect to see him behind the dish a little more often. That will only boost his WAR. To boot, guys who walk and hit for average tend to age very gracefully as long as they don't suffer career-ending injuries. Don't get me wrong, both Mauer and Fielder are risks aging into their 30s (as is everyone, really) but given Mauer's athleticism, physique, and high contact rate, I think he'll be just fine for several more years. I can't say the same for Prince, who could easily go the route of his father overnight.