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Brian Westbrook + Correll Buckhalter for Marion Barber + Felix Jones + DeSean Jackson

Westy is definitely the best player in the trade, but Barber isn't far behind him. Barber scores more TDs, he's younger and less injury prone, and he's starting for the first time this year so his stats will only increase.

As far the filler, Buckhalter has zero value unless Westbrook goes down. On the other hand, Felix Jones will probably get alot of carries this year, and DeSean Jackson is going to be the top WR for the Eagles (with Curtis out).

I'm in a standard 12 team head-to head league.

Thoughts?

You said it yourself, the Barber/Jones/Jackson part of the deal should definitely garner more points that Westbrook and Bucky.

3 is better than 2, well in this case

The team getting the best player wins 90% of fantasy football trades. This really comes down to whether you like Westbrook or Barber more.

Felix Jones has no value in addition to Barber because you sure as hell aren't going to ever start them both unless your team is in a very sorry state RB wise. DeSean Jackson isn't in the top 150 for ADP, so while he's a viable sleeper, he adds basically no value to the trade. There are probably 40+ WRs in the league who have as much value or more right now.

If Westbrook outperforms Barber than the the side getting Westbrook wins the trade unless DeSean Jackson miraculously puts up a 900-1000 yard 6+ TD season (I'd be shocked if that happened). If Barber outperforms Westbrook then his side wins the trade. Simple as that. The additional stuff thrown in on both sides is meaningless IMO.

-edit to add-
If it's a keeper / dynasty league then that might change things up and give more value to the Barber side of the deal due to youth.