Add User Group Based on Country

I am looking for a way to automatically add a user group to a new account signup based on the country of the new accounts shipping address.

I have wasted a lot of time with the Localization feature and after receiving a lost of customer complaints I am ready to give up on it because it is faulty, but I may be able to use user groups to accomplish product restrictions for certain destinations if I can automatically apply a user group to an new account sign up.