It depends on the time of year with Amazon I think. When Christmas gets close, they seem so keen to get everything out in time, it pretty much flies out the door ASAP, often regardless of which delivery level you booked. I have an order of two items in transit at the moment, which were dispatched separately "to prevent delay" as sometimes happens - although the emails show the items left the warehouse about 90 minutes apart, are both due to arrive on the same day, and one of them is a sub-£3 "add on" item that is only meant to come with a larger order. It will probably cost them as much in courier charges as I paid for the item.
As for who is any good coming out here to our slightly out-of-the-way rural address, well all the regular drivers for all the main companies are reliable and they know where to leave stuff if we're not here. The exceptions are relief drivers covering days off, who frequently report "delivery attempted" without ever coming within 10 miles of us, and Parcel Farce, who are lazy gits who take advantage of the local RM delivery office - they leave the package down there and then put the calling card in the post bag, so we get the card the next day, and then have to drive down there to get the parcel.