Do not fall for spending the extra $35 to protect your flight in case you have to change or cancel.
They will give you every excuse not to give you back your money. Literally had to hound them for 2 months just to get a partial refund (countless emails, hour upon hours of phone conversations with customer support, and even using the prehistoric fax machine).
I would highly recommend avoiding booking flights with expedia in general but if you have to you better be 99.9% sure you won't have to cancel or change flight because their protection plan is absolutely worthless.