Some guy in my league offered me Clinton Portis and Mario Manningham for Donald Driver and Lendale White. Is this a good trade?

For some perspective, my team is 5-0 so I'm sort of looking more to the playoffs than you usually would. This is a .5 PPR league with bonus points for 100 yards rushing/receiving and 150 yards rushing/receiving. Here's my team:

QB: Schaub, Big Ben

RB: Barber, Lynch, Moreno, Washington, Lenwhale, Jamaal Charles

WR: Calvin Johnson, Reggie Wayne, Roddy White, Donald Driver, Bobby Wade

TE: Jason Witten, Donald Lee

The only other thing is that this is a keeper contract league. Lendale White has a 2 year contract and all of the other guys involved have 1 year deals. So is it worth trading 2 years of Lenwhale and 1 year of Driver for 1 year of Portis and Manningham?