in bank, you can take your contributions without penalty or admin fees.
with USC or other similar organizations, if you withdraw earlier you will pay penalty or admin fees, usually it is thousands of dollars,depends how long and how much you put in it. and if you withdraw from RESP, the benefits part will be put back to the government. so you can only get your contributions, I am not sure that you can get your interest or not. In bank, I think you can, with USC probably not.
the only thing about USC is better that the returns usually much higher than bank.