So my Mail Drop boxes are sitting here in their "Free from the Post Office" Priority Mail Boxes and I'm wondering ... Should I use First Class or Priority Mail to mail them? Do you recommend UPS/FedEx if they're not going to a Post Office? I know SOME of the places that accept Mail Drops request UPS or non-USPS delivery, but not all.

What't's the consensus? What worked for you former Thrus and what works for you Section Hikers?

Thanks for the input.
Coosa