The contractor will be drafting. You will learn exactly how buildings (prob houses) go together and the things that contractors want to have happen. It probably won't be on architect designed buildings. It will be a good technical-and "other side of the table" education. Other architects may see this as "lesser" experience and by proxy assume you aren't as good either. The design studio may offer you similar experience in technical drafting-especially if you ask for it. Or if they are more design oriented you may be doing models, 3d rendering, sketching. Have you considered getting a position for a developer ?
mnja24: Please tell us what the contractor says your duties will be? And, how long would you would expect to work there?