As one who ships every week I will chime in about the no live arrival on priority thing. The reason for this is that in teh fine print for priority it says it can take something like up to 10 days with 2-3 days being typical. Most packages arrive in 2-3 days which is "safe" for smaller fish if packaged well. The other thing is that usps will not insure live fish. So if a seller ships priority and it ends up taking 7 days instead of 2 (no fault of the seller) and the fish arrive dead, there is no way for the seller to recover their money. same goes for express except you can at least get your shipping money back if its over 2 days. I ship small fish priority alot and almost always ship invertebrates priority. I have a super high live arrival rate, but I still cannot guarantee live arrival on priority (especially this time of year with the holidays approaching). I prefer express. Airport to airport for large or valuable fish.