Posted By:
FatBoyWhen I send in a box of cards for grading, I usually use USPS registered.
I found for big dollar boxes....$3000-5000 for instance, the insurance is so much cheaper as compared to priority with insurance and tracking number. I'm guessing because of the kid gloves that are used for registered. The girl at the post office told me all registered mail is put in a special bag and handled separately from regular mail be it priority or otherwise. It just feels "safer" to me with registered. You also get automatic priority and tracking.
As a side....The first time I sent registered (I used the plastic stuff), she applied paper tape to all box seams and a rubber stamp was used to span the seam of the tape and the box with a date and initial mailing location. She then asked me if I was going to be mailing anything else registered in the future.....and when I told her I would be, she gave me a roll of the paper tape, a stack of registered mail forms and tells me every time I come in "I see you're making good use of that tape I gave ya" 
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