Update on those shipped eggs.... Overall 154 silkie & faverolle, 14 peafowl, and 5 goose eggs. 2 shipments, both in Horizon boxes with express mail just like they are live birds. Total shipping cost with 2 boxes $165. All were individually bubble wrapped and then taped in cartons so they had to stay large end up. Boxes were stuffed with shavings and bubble wrap so nothing moved at all. The first shipment went out when it was in the 70's up here and the 2nd went out on a day when it hit 103 here. The buyer got back to me with some results already. Only 1 egg out of all of them was cracked, rest were all in great condition. No air cells broken. She even shipped 2 dozen of those first eggs to a friend of hers as well. I personally get about 70% fertility here at home. On the 1st batch of shipped eggs, the buyer reported 60% for herself and 65% for her friend (the double shipped eggs). On the 2nd batch, she's reported 73% so far.
I think if you are willing to spend the extra money on express mail and ship like you would live birds, those packages aren't bounced around on a conveyor belt. Even on a day where it hit 103 here, the post office treated them like lives and didn't expose them to extreme temps back in a cargo hold or rear end of a truck all day.