The thing I'd worry about with Wells is his health--specifically, his back. It's a question mark for me how many innings he'll provide, since he'll be 42 soon, after all. But I think that every year, and every year for the last few years he's proved me wrong, and I think he's averaged around 200 IP in the last few years. He definitely won't kill your WHIP - the guy walks like 25 batters a year. But switching from the NL West (and Petco Park) to the AL East? I imagine his ERA and (already low) WHIP to rise, and so will his wins with a better team (15?), IF he stays healthy. His WHIP will still be above-average I bet, with that wicked control.