Dunn is very likely going to be at least a 100 point upgrade in OPS over Murton. Having Murton put up a 780-800 OPS might be more cost effective, but we'd be better off spending to get Dunn to consistently put up a 900+ OPS. I wouldn't say he would be at least a 100 plus upgrade necessarily. Dunn has put up a 900 or more 2 out of the last 4 years-one of the years he didn't do that was this year. He's 89 points better than Murton this year. Murton's numbers still have room to go up, while Dunn is more likely to consistently stay around the numbers he's put up the last 3-4 seasons or so. Dunn is 26, Murton is 24. Dunn makes 7.5 million dollars this year, Murton makes 337,000. Murton plays better defense than Dunn (although Dunn is a little better than some of the mistakes we see him make on defense). Also, trading for Dunn would require more than Murton-so we have to factor in how valuable the other players we'd have to trade them would be, or how valuable those pieces would be in another trade (some of the players mentioned could be used to get Andruw Jones or possibly Tejada for example) It still might be worth the gamble, but it's certainly not an open and shut case. Why would you expect a 24-year-old Murton to improve but not a 26-year-old Dunn?