Admittedly, I don't have much to go on for Fuku other than the reports I've read and a few scattered video clips, but all indications he'd be a monumental upgrade over Murton, who's a butcher in RF. “Fukudome is one of the better athletes playing in Japan. He is capable of playing center field and right field...20–30 HR, 80–100 RBI and 10 SB.” - Scout Mike Pagliarulo "He plays very hard; he’ll be strong defensively in right field, where he has a great arm, very similar to Ichiro" - MLB team official Replacing one of the worst defensive RFs in the league with a terrific fielder (trusting the reports) will have a profound effect, especially at Wrigley, one of the tougher RFs to play in the game, and would be a huge benefit for Lilly and Hill's flyball tendencies. Roberts would be an upgrade defensively, but 2B is too unimportant defensively and the gap in talent too marginal to mention. However, the speed difference between the two is about as stark a contrast as you can get. Having Roberts on base instead of Derosa would factor into play different pitches the following hitters will be seeing, as well as easier RBI opportunities when he steals bases and takes the extra base. There's no easily quantifiable area where the replacement of Derosa and Murton with Roberts and Fukudome, but factoring the vastly improved RF defense, significant speed upgrade at 2nd, in addition to half a dozen other smaller but not insignificant factors (reliable production, added speed and power in RF, improved bench, added LH balance to order, we'd be a significantly improved team with the addition of Roberts and Fukudome. Leave it to the guy with the caveman avatar to talk about speediness and lineup balance. I can't say I didn't expect a response like this.