Both had similar xFIP, innings, k/9, but Gibson was a much more consistent innings eater. With Sale and Paxton projected to be part of the rotation, they would need someone certain to pick up the slack for two guys coming off injuries and may be limited. Gibson is a 30 game a year guy. He's going to take the ball every 5th day. With Kluber, there was still the question mark of the recent injury history and age catching up to him. Gibson is the ground ball, pitch to contact guy who you know what you're going to get out of year to year. That rotation needed more consistency. We even said so last offseason. Kluber, Paxton and Sale in the rotation at the same time was a significant amount of uncertainty. Gibson isn't a sexy FA signing, but he's a Porcello type that can get you to the pen in good shape most days.