If anything ever doesn't arrive I go around the corner, about 50 yards on the other side of the road and knock on the door of the guy with the same name as me. Most of the time it's there, he never bothers to pop it round to me. Anything else I ask in the local PO, they know me personally so it's not a problem. I've never had anything expensive go awry, fortunately.
Whilst I may get a relatively good service out of them (fingers crossed, touch wood, and all that), there are two regular postwomen in my village who are the grumpiest posties ever - barely a grumble if you say, 'Good Morning!' in your annoyingly cheeriest voice. Stopped them cutting across my lawn and over the fence to my neighbours - if they had an ounce of decency or personality I'd let them carry on.