The answer is....it depends. It depends if you need to purchase your tickets through Disney in order to take advantage of a package deal like FREE dining. It depends on the number of days, if you want to hop, if you want to go to PI, DQ, BB, & TL, if you need for the tickets to not expire. It depends if you are planning trips in the course of a year that would put you in the parks more than 11 days. It depends on if you need adult vs kids tickets. It depends on if you need them delivered to your home or your resort.
Lots of variables to consider. Sorry, there is no one answer that is right for everyone. Maggie