You can get a different QB1 on the cheap, if Romo struggles. Your RB's are not strong enough to survive without Charles.
This owner is looking to punk you with this trade, not only get the best players but also get a QB back from you and he doesn't have to give back a RB. Make 0 sense! You can get a much better trade for Charles.
try to get an RB2 along with Manning. I wouldn't bank on any of your RBs except Foster.
Based on your logic, go for it. I think you made a good argument for the trade. If you are able to justify the trade in your head, then it is a good trade.