So I live here in the Great White North (of the US) in Maine and the shipping during winter bothers me. I have heard of this 40 hour heat pack but we routinely have overnight packages that don't make it here overnight (about 50%). So is 48 hours too long? I read somewhere that for cold climate cities, having shipments held at a regional office would be safe. I'm thinking May - October would be safest or am I just a worry wort? What says everyone?