With a College Career behind him, and his two seasons of missed time during his prime years, it's very possible that he does not have a lot of playing time on those wheels that would make "30" seem like the age that it is. He could very easily produce five very good years, but most likely will give a team 3-1/2. But, with Scott Boras his agent, there's no way he settles for five years.
Boras will target at least 7 years, and consequently, someone will overpay as you say.
He's currently second in the AL in UZR/150 in CenterField, leads the league in Triples and Stolen Bases. So, maybe he has recovered physically from his injuries.
I'd take him over Choo in a heartbeat, as I highly value Defense. But, Choo would be a better contract.