Are there any customs issues if you ship to CGC for grading from Canada? 0

[My60sComics]

Has anyone shipped comics to CGC for grading from Canada? If so, are there any customs issues to be concerned about, either going from Canada to the U.S., or from the U.S. back into Canada?

For example, if you quote a value of $US 200 on your shipment to CGC on the customs form (e.g. because you want to insure your shipment) will you have to pay duty on the shipment when it comes back to you, assuming that CGC assigns a $US 200 value to the shipment? Are there any differences between using Canada Post vs. Fedex or UPS?

Alternatively, I could ship the books from the U.S. (I live 45 minutes from the border) and receive them in the U.S. and deal with the customs issues myself.

Thanks in advance for any advice!