I have Jamal Lewis on my squad as well, (Freeman too) and I have been considering shopping them around. But after looking for trades and not seeing much, I have decided so far to hold on and see how they do.
Freeman will get some TD's pretty soon, he won't need much time before he move up to #2 or 1 and his value should rise. Lewis is a ? but there are alot of those this year. Just have a decent #3 RB and hope, hope, hope. If he has a good first game (which is likely against Carolina) his value should rise too - shop him after that game or decide to hold on.