I would go for it.
Hernandez is an obvious upgrade at SS. He will give you a good amount of Hr's, Rbi, a decent avg, and a couple SB's. He does K, A LOT, so if K's count in your league and you have a couple high K batters already, that could hurt you.
Ibanez, I believe, will be solid again this year. I would look for him to approach last years numbers. I don't think he will better them, but he should be close to last year.
As for Thomas, I have him in almost all of my leagues. I expect him to have a good bounceback year. I expect somewhere about
.285/34/105 from him. He also walks a good amount, so if BB's count in your league, be prepared to lose about 90 BB's. Hernandez and Ibanez combined to close to 90 BB's last year, so that really might hurt. As far as power numbers, I still think you come out ahead, it's the BB's, and OBP numbers that you might slip in.
'When I'm not longer rapping, I want to open up an ice cream parlor and call myself Scoop Dogg.'
-Snoop on his retirement
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