I don’t think ‘winning’ a trade like this in the moment is exactly the goal. Sure, who doesn’t want to sell high and I don’t want to waste assets, but we traded Sale+$ to get Grissom. We traded Pavano+ for Pedro.Theoretically, you would "sell high" on pretty much anyone, no? If someone is willing to offer you more value than you attribute to a player, then you make the deal. Of course how one team values a player will frequently by different than how another team does, making trades in general a worthwhile pursuit.
In terms of what Duran brings or will bring to the Sox, I think, as others have said, that he will continue to post high BABIP numbers consistently, but also a decent OPS despite not hitting many homers or walking at a high rate. I see it fueled by that BABIP and his ability to turn singles into doubles and doubles into triples with his footspeed. That won't last forever, and it might make him more injury-prone as he'll be in full-sprint mode more than someone who doesn't rely on beating out or stretching hits, but why not get fun, productive, and unique (in this day) production on the cheap?
Unless of course some other team overvalues him. Then you move him.
They are all kind of lottery tickets, but you should plan to give up quality to get it, and be mostly interested in the return: particularly assuming you are trading from depth for need.