Pretty unhelpful guys - he is asking who has had problems, not who hasn't!
I've had two or three stopped by customs, as they switch from mail handler to mail handler the tracking numbers are not carried forwards sometimes. In my experience anything that comes in from overseas, Parcelforce have ultimate responsibility for dealing with and delivering to its final destination.
As I said, I have had about three held up by these idiots who it seems have a licence to print money. If customs give the package a tug, Parcelforce will hold delivery in abeyance. They will then contact you asking for an import levy (