One thing I have noticed when making an online purchase is that delivery most often comes sooner than expected when choosing the least expensive delivery option. So unless I really need something quickly I go for the cheaper shipping method. My theory is that the shipper probably processes all orders the same way and although you may choose a delivery option for up to 21 days it goes out right away and the carrier doesn’t hold on to it either, so you usually get the item in 3-4 days.