A mate of mine decided to Test the postal service at the end of last year and send Christmas cards by post from PE
He posted them on 14th Nov

Sent 2 cards PE to PE - so far 1 arrived ( 10th Jan )
Sent 6 PE to KZN /Durban - 3 arrived ( 10th Jan /30 Jan/ 21 Feb )
Sent 2 PE to Aus /UK - 0 arrived

Out of 10 sent so far only 4 have arrived -

Under a 50% success rate on delivery and a complete failure on the promised 3 day delivery service in SA and a 10 day delivery service overseas