Anyone had any problems with Royal Mail "losing" mail.

We have had problems with missing mail since about August.When I report it to Royal Mail I just get a PPO letter (polite p### off)

Several items have now gone missing in the run up to Christmas.Its not the weather either because every item delivered by Courier has been delivered but things sent by Royal Mail seem to go missing.Someone told me that RM employ a lot of casual staff in the run up to Christmas through employment agencies that do not check up on their applicant.
Some view working at RM as an opportunity to pilfer other peoples stuff.

I have got to the point of not sending out items by Royal Mail and always use a courier instead. If its urgent and fairly local I will take it myself as at least I know it arrives ok.